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@pzakha pzakha commented Feb 4, 2021

@pzakha pzakha merged commit 046098e into delphix:master Feb 9, 2021
delphix-devops-bot pushed a commit that referenced this pull request Mar 20, 2021
… runtime suspended

BugLink: https://bugs.launchpad.net/bugs/1906851

Similar to commit 165ae7a ("igb: Report speed and duplex as unknown
when device is runtime suspended"), if we try to read speed and duplex
sysfs while the device is runtime suspended, igc will complain and
stops working:

[  123.449883] igc 0000:03:00.0 enp3s0: PCIe link lost, device now detached
[  123.450052] BUG: kernel NULL pointer dereference, address: 0000000000000008
[  123.450056] #PF: supervisor read access in kernel mode
[  123.450058] #PF: error_code(0x0000) - not-present page
[  123.450059] PGD 0 P4D 0
[  123.450064] Oops: 0000 [#1] SMP NOPTI
[  123.450068] CPU: 0 PID: 2525 Comm: udevadm Tainted: G     U  W  OE     5.10.0-1002-oem #2+rkl2-Ubuntu
[  123.450078] RIP: 0010:igc_rd32+0x1c/0x90 [igc]
[  123.450080] Code: c0 5d c3 b8 fd ff ff ff c3 0f 1f 44 00 00 0f 1f 44 00 00 55 89 f0 48 89 e5 41 56 41 55 41 54 49 89 c4 53 48 8b 57 08 48 01 d0 <44> 8b 28 41 83 fd ff 74 0c 5b 44 89 e8 41 5c 41 5d 4

[  123.450083] RSP: 0018:ffffb0d100d6fcc0 EFLAGS: 00010202
[  123.450085] RAX: 0000000000000008 RBX: ffffb0d100d6fd30 RCX: 0000000000000000
[  123.450087] RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff945a12716c10
[  123.450089] RBP: ffffb0d100d6fce0 R08: ffff945a12716550 R09: ffff945a09874000
[  123.450090] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000008
[  123.450092] R13: ffff945a12716000 R14: ffff945a037da280 R15: ffff945a037da290
[  123.450094] FS:  00007f3b34c868c0(0000) GS:ffff945b89200000(0000) knlGS:0000000000000000
[  123.450096] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  123.450098] CR2: 0000000000000008 CR3: 00000001144de006 CR4: 0000000000770ef0
[  123.450100] PKRU: 55555554
[  123.450101] Call Trace:
[  123.450111]  igc_ethtool_get_link_ksettings+0xd6/0x1b0 [igc]
[  123.450118]  __ethtool_get_link_ksettings+0x71/0xb0
[  123.450123]  duplex_show+0x74/0xc0
[  123.450129]  dev_attr_show+0x1d/0x40
[  123.450134]  sysfs_kf_seq_show+0xa1/0x100
[  123.450137]  kernfs_seq_show+0x27/0x30
[  123.450142]  seq_read+0xb7/0x400
[  123.450148]  ? common_file_perm+0x72/0x170
[  123.450151]  kernfs_fop_read+0x35/0x1b0
[  123.450155]  vfs_read+0xb5/0x1b0
[  123.450157]  ksys_read+0x67/0xe0
[  123.450160]  __x64_sys_read+0x1a/0x20
[  123.450164]  do_syscall_64+0x38/0x90
[  123.450168]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  123.450170] RIP: 0033:0x7f3b351fe142
[  123.450173] Code: c0 e9 c2 fe ff ff 50 48 8d 3d 3a ca 0a 00 e8 f5 19 02 00 0f 1f 44 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 0f 05 <48> 3d 00 f0 ff ff 77 56 c3 0f 1f 44 00 00 48 83 ec 28 48 89 54 24
[  123.450174] RSP: 002b:00007fffef2ec138 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[  123.450177] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3b351fe142
[  123.450179] RDX: 0000000000001001 RSI: 00005644c047f070 RDI: 0000000000000003
[  123.450180] RBP: 00007fffef2ec340 R08: 00005644c047f070 R09: 00007f3b352d9320
[  123.450182] R10: 00005644c047c010 R11: 0000000000000246 R12: 00005644c047cbf0
[  123.450184] R13: 00005644c047e6d0 R14: 0000000000000003 R15: 00007fffef2ec140
[  123.450189] Modules linked in: rfcomm ccm cmac algif_hash algif_skcipher af_alg bnep toshiba_acpi industrialio toshiba_haps hp_accel lis3lv02d btusb btrtl btbcm btintel bluetooth ecdh_generic ecc joydev input_leds nls_iso8859_1 snd_sof_pci snd_sof_intel_byt snd_sof_intel_ipc snd_sof_intel_hda_common snd_soc_hdac_hda snd_hda_codec_hdmi snd_sof_xtensa_dsp snd_sof_intel_hda snd_sof snd_hda_ext_core snd_soc_acpi_intel_match snd_soc_acpi snd_hda_codec_realtek snd_hda_codec_generic ledtrig_audio snd_hda_intel snd_intel_dspcfg soundwire_intel soundwire_generic_allocation soundwire_cadence snd_hda_codec snd_hda_core ath10k_pci snd_hwdep intel_rapl_msr intel_rapl_common ath10k_core soundwire_bus snd_soc_core x86_pkg_temp_thermal ath intel_powerclamp snd_compress ac97_bus snd_pcm_dmaengine mac80211 snd_pcm coretemp snd_seq_midi snd_seq_midi_event snd_rawmidi kvm_intel cfg80211 snd_seq snd_seq_device snd_timer mei_hdcp kvm libarc4 snd crct10dif_pclmul ghash_clmulni_intel aesni_intel
 mei_me dell_wmi
[  123.450266]  dell_smbios soundcore sparse_keymap dcdbas crypto_simd cryptd mei dell_uart_backlight glue_helper ee1004 wmi_bmof intel_wmi_thunderbolt dell_wmi_descriptor mac_hid efi_pstore acpi_pad acpi_tad intel_cstate sch_fq_codel parport_pc ppdev lp parport ip_tables x_tables autofs4 btrfs blake2b_generic raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 multipath linear dm_mirror dm_region_hash dm_log hid_generic usbhid hid i915 i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec crc32_pclmul rc_core drm intel_lpss_pci i2c_i801 ahci igc intel_lpss i2c_smbus idma64 xhci_pci libahci virt_dma xhci_pci_renesas wmi video pinctrl_tigerlake
[  123.450335] CR2: 0000000000000008
[  123.450338] ---[ end trace 9f731e38b53c35cc ]---

The more generic approach will be wrap get_link_ksettings() with begin()
and complete() callbacks, and calls runtime resume and runtime suspend
routine respectively. However, igc is like igb, runtime resume routine
uses rtnl_lock() which upper ethtool layer also uses.

So to prevent a deadlock on rtnl, take a different approach, use
pm_runtime_suspended() to avoid reading register while device is runtime
suspended.

Cc: <[email protected]>
Signed-off-by: Kai-Heng Feng <[email protected]>
Acked-by: Sasha Neftin <[email protected]>
(cherry picked from commit 0636cd13c6e5e025c95374a78b68c6dc86693fb4 git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/next-queue.git dev-queue)
Signed-off-by: Kai-Heng Feng <[email protected]>
Acked-by: Stefan Bader <[email protected]>
Acked-by: Kleber Sacilotto de Souza <[email protected]>
Signed-off-by: Ian May <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request Mar 20, 2021
BugLink: https://bugs.launchpad.net/bugs/1908562

[ Upstream commit e773ca7 ]

Actually, burst size is equal to '1 << desc->rqcfg.brst_size'.
we should use burst size, not desc->rqcfg.brst_size.

dma memcpy performance on Rockchip RV1126
@ 1512MHz A7, 1056MHz LPDDR3, 200MHz DMA:

dmatest:

/# echo dma0chan0 > /sys/module/dmatest/parameters/channel
/# echo 4194304 > /sys/module/dmatest/parameters/test_buf_size
/# echo 8 > /sys/module/dmatest/parameters/iterations
/# echo y > /sys/module/dmatest/parameters/norandom
/# echo y > /sys/module/dmatest/parameters/verbose
/# echo 1 > /sys/module/dmatest/parameters/run

dmatest: dma0chan0-copy0: result #1: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000
dmatest: dma0chan0-copy0: result #2: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000
dmatest: dma0chan0-copy0: result #3: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000
dmatest: dma0chan0-copy0: result #4: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000
dmatest: dma0chan0-copy0: result #5: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000
dmatest: dma0chan0-copy0: result #6: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000
dmatest: dma0chan0-copy0: result #7: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000
dmatest: dma0chan0-copy0: result #8: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000

Before:

  dmatest: dma0chan0-copy0: summary 8 tests, 0 failures 48 iops 200338 KB/s (0)

After this patch:

  dmatest: dma0chan0-copy0: summary 8 tests, 0 failures 179 iops 734873 KB/s (0)

After this patch and increase dma clk to 400MHz:

  dmatest: dma0chan0-copy0: summary 8 tests, 0 failures 259 iops 1062929 KB/s (0)

Signed-off-by: Sugar Zhang <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Vinod Koul <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
Signed-off-by: Ian May <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request Mar 20, 2021
BugLink: https://bugs.launchpad.net/bugs/1910816

commit 190113b upstream.

Prarit reported that depending on the affinity setting the

 ' irq $N: Affinity broken due to vector space exhaustion.'

message is showing up in dmesg, but the vector space on the CPUs in the
affinity mask is definitely not exhausted.

Shung-Hsi provided traces and analysis which pinpoints the problem:

The ordering of trying to assign an interrupt vector in
assign_irq_vector_any_locked() is simply wrong if the interrupt data has a
valid node assigned. It does:

 1) Try the intersection of affinity mask and node mask
 2) Try the node mask
 3) Try the full affinity mask
 4) Try the full online mask

Obviously #2 and #3 are in the wrong order as the requested affinity
mask has to take precedence.

In the observed cases #1 failed because the affinity mask did not contain
CPUs from node 0. That made it allocate a vector from node 0, thereby
breaking affinity and emitting the misleading message.

Revert the order of #2 and #3 so the full affinity mask without the node
intersection is tried before actually affinity is broken.

If no node is assigned then only the full affinity mask and if that fails
the full online mask is tried.

Fixes: d6ffc6a ("x86/vector: Respect affinity mask in irq descriptor")
Reported-by: Prarit Bhargava <[email protected]>
Reported-by: Shung-Hsi Yu <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Tested-by: Shung-Hsi Yu <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
Signed-off-by: Kelsey Skunberg <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request Mar 20, 2021
BugLink: https://bugs.launchpad.net/bugs/1910816

commit e91d8d7 upstream.

While I was doing zram testing, I found sometimes decompression failed
since the compression buffer was corrupted.  With investigation, I found
below commit calls cond_resched unconditionally so it could make a
problem in atomic context if the task is reschedule.

  BUG: sleeping function called from invalid context at mm/vmalloc.c:108
  in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 946, name: memhog
  3 locks held by memhog/946:
   #0: ffff9d01d4b193e8 (&mm->mmap_lock#2){++++}-{4:4}, at: __mm_populate+0x103/0x160
   #1: ffffffffa3d53de0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath.constprop.0+0xa98/0x1160
   #2: ffff9d01d56b8110 (&zspage->lock){.+.+}-{3:3}, at: zs_map_object+0x8e/0x1f0
  CPU: 0 PID: 946 Comm: memhog Not tainted 5.9.3-00011-gc5bfc0287345-dirty #316
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1 04/01/2014
  Call Trace:
    unmap_kernel_range_noflush+0x2eb/0x350
    unmap_kernel_range+0x14/0x30
    zs_unmap_object+0xd5/0xe0
    zram_bvec_rw.isra.0+0x38c/0x8e0
    zram_rw_page+0x90/0x101
    bdev_write_page+0x92/0xe0
    __swap_writepage+0x94/0x4a0
    pageout+0xe3/0x3a0
    shrink_page_list+0xb94/0xd60
    shrink_inactive_list+0x158/0x460

We can fix this by removing the ZSMALLOC_PGTABLE_MAPPING feature (which
contains the offending calling code) from zsmalloc.

Even though this option showed some amount improvement(e.g., 30%) in
some arm32 platforms, it has been headache to maintain since it have
abused APIs[1](e.g., unmap_kernel_range in atomic context).

Since we are approaching to deprecate 32bit machines and already made
the config option available for only builtin build since v5.8, lastly it
has been not default option in zsmalloc, it's time to drop the option
for better maintenance.

[1] http://lore.kernel.org/linux-mm/[email protected]

Fixes: e47110e ("mm/vunmap: add cond_resched() in vunmap_pmd_range")
Signed-off-by: Minchan Kim <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Reviewed-by: Sergey Senozhatsky <[email protected]>
Cc: Tony Lindgren <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Harish Sriram <[email protected]>
Cc: Uladzislau Rezki <[email protected]>
Cc: <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
Signed-off-by: Kelsey Skunberg <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request Mar 20, 2021
…d ops

BugLink: https://bugs.launchpad.net/bugs/1910822

[ Upstream commit 52719fc ]

There are three ways pseries_suspend_begin() can be reached:

1. When "mem" is written to /sys/power/state:

kobj_attr_store()
-> state_store()
  -> pm_suspend()
    -> suspend_devices_and_enter()
      -> pseries_suspend_begin()

This never works because there is no way to supply a valid stream id
using this interface, and H_VASI_STATE is called with a stream id of
zero. So this call path is useless at best.

2. When a stream id is written to /sys/devices/system/power/hibernate.
pseries_suspend_begin() is polled directly from store_hibernate()
until the stream is in the "Suspending" state (i.e. the platform is
ready for the OS to suspend execution):

dev_attr_store()
-> store_hibernate()
  -> pseries_suspend_begin()

3. When a stream id is written to /sys/devices/system/power/hibernate
(continued). After #2, pseries_suspend_begin() is called once again
from the pm core:

dev_attr_store()
-> store_hibernate()
  -> pm_suspend()
    -> suspend_devices_and_enter()
      -> pseries_suspend_begin()

This is redundant because the VASI suspend state is already known to
be Suspending.

The begin() callback of platform_suspend_ops is optional, so we can
simply remove that assignment with no loss of function.

Fixes: 32d8ad4 ("powerpc/pseries: Partition hibernation support")
Signed-off-by: Nathan Lynch <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
Signed-off-by: Kelsey Skunberg <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request Mar 20, 2021
BugLink: https://bugs.launchpad.net/bugs/1910822

[ Upstream commit 4a9d81c ]

If the elem is deleted during be iterated on it, the iteration
process will fall into an endless loop.

kernel: NMI watchdog: BUG: soft lockup - CPU#4 stuck for 22s! [nfsd:17137]

PID: 17137  TASK: ffff8818d93c0000  CPU: 4   COMMAND: "nfsd"
    [exception RIP: __state_in_grace+76]
    RIP: ffffffffc00e817c  RSP: ffff8818d3aefc98  RFLAGS: 00000246
    RAX: ffff881dc0c38298  RBX: ffffffff81b03580  RCX: ffff881dc02c9f50
    RDX: ffff881e3fce8500  RSI: 0000000000000001  RDI: ffffffff81b03580
    RBP: ffff8818d3aefca0   R8: 0000000000000020   R9: ffff8818d3aefd40
    R10: ffff88017fc03800  R11: ffff8818e83933c0  R12: ffff8818d3aefd40
    R13: 0000000000000000  R14: ffff8818e8391068  R15: ffff8818fa6e4000
    CS: 0010  SS: 0018
 #0 [ffff8818d3aefc98] opens_in_grace at ffffffffc00e81e3 [grace]
 #1 [ffff8818d3aefca8] nfs4_preprocess_stateid_op at ffffffffc02a3e6c [nfsd]
 #2 [ffff8818d3aefd18] nfsd4_write at ffffffffc028ed5b [nfsd]
 #3 [ffff8818d3aefd80] nfsd4_proc_compound at ffffffffc0290a0d [nfsd]
 #4 [ffff8818d3aefdd0] nfsd_dispatch at ffffffffc027b800 [nfsd]
 #5 [ffff8818d3aefe08] svc_process_common at ffffffffc02017f3 [sunrpc]
 #6 [ffff8818d3aefe70] svc_process at ffffffffc0201ce3 [sunrpc]
 #7 [ffff8818d3aefe98] nfsd at ffffffffc027b117 [nfsd]
 #8 [ffff8818d3aefec8] kthread at ffffffff810b88c1
 #9 [ffff8818d3aeff50] ret_from_fork at ffffffff816d1607

The troublemake elem:
crash> lock_manager ffff881dc0c38298
struct lock_manager {
  list = {
    next = 0xffff881dc0c38298,
    prev = 0xffff881dc0c38298
  },
  block_opens = false
}

Fixes: c87fb4a ("lockd: NLM grace period shouldn't block NFSv4 opens")
Signed-off-by: Cheng Lin <[email protected]>
Signed-off-by: Yi Wang <[email protected]>
Signed-off-by: Chuck Lever <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
Signed-off-by: Kelsey Skunberg <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request Mar 20, 2021
BugLink: https://bugs.launchpad.net/bugs/1915186

[ Upstream commit b774134 ]

The buffer list can have zero skb as following path:
tipc_named_node_up()->tipc_node_xmit()->tipc_link_xmit(), so
we need to check the list before casting an &sk_buff.

Fault report:
 [] tipc: Bulk publication failure
 [] general protection fault, probably for non-canonical [#1] PREEMPT [...]
 [] KASAN: null-ptr-deref in range [0x00000000000000c8-0x00000000000000cf]
 [] CPU: 0 PID: 0 Comm: swapper/0 Kdump: loaded Not tainted 5.10.0-rc4+ #2
 [] Hardware name: Bochs ..., BIOS Bochs 01/01/2011
 [] RIP: 0010:tipc_link_xmit+0xc1/0x2180
 [] Code: 24 b8 00 00 00 00 4d 39 ec 4c 0f 44 e8 e8 d7 0a 10 f9 48 [...]
 [] RSP: 0018:ffffc90000006ea0 EFLAGS: 00010202
 [] RAX: dffffc0000000000 RBX: ffff8880224da000 RCX: 1ffff11003d3cc0d
 [] RDX: 0000000000000019 RSI: ffffffff886007b9 RDI: 00000000000000c8
 [] RBP: ffffc90000007018 R08: 0000000000000001 R09: fffff52000000ded
 [] R10: 0000000000000003 R11: fffff52000000dec R12: ffffc90000007148
 [] R13: 0000000000000000 R14: 0000000000000000 R15: ffffc90000007018
 [] FS:  0000000000000000(0000) GS:ffff888037400000(0000) knlGS:000[...]
 [] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 [] CR2: 00007fffd2db5000 CR3: 000000002b08f000 CR4: 00000000000006f0

Fixes: af9b028 ("tipc: make media xmit call outside node spinlock context")
Acked-by: Jon Maloy <[email protected]>
Signed-off-by: Hoang Le <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
Signed-off-by: William Breathitt Gray <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request Mar 20, 2021
BugLink: https://bugs.launchpad.net/bugs/1915195

commit fb28610 upstream.

While testing the error paths of relocation I hit the following lockdep
splat:

  ======================================================
  WARNING: possible circular locking dependency detected
  5.10.0-rc6+ #217 Not tainted
  ------------------------------------------------------
  mount/779 is trying to acquire lock:
  ffffa0e676945418 (&fs_info->balance_mutex){+.+.}-{3:3}, at: btrfs_recover_balance+0x2f0/0x340

  but task is already holding lock:
  ffffa0e60ee31da8 (btrfs-root-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x27/0x100

  which lock already depends on the new lock.

  the existing dependency chain (in reverse order) is:

  -> #2 (btrfs-root-00){++++}-{3:3}:
	 down_read_nested+0x43/0x130
	 __btrfs_tree_read_lock+0x27/0x100
	 btrfs_read_lock_root_node+0x31/0x40
	 btrfs_search_slot+0x462/0x8f0
	 btrfs_update_root+0x55/0x2b0
	 btrfs_drop_snapshot+0x398/0x750
	 clean_dirty_subvols+0xdf/0x120
	 btrfs_recover_relocation+0x534/0x5a0
	 btrfs_start_pre_rw_mount+0xcb/0x170
	 open_ctree+0x151f/0x1726
	 btrfs_mount_root.cold+0x12/0xea
	 legacy_get_tree+0x30/0x50
	 vfs_get_tree+0x28/0xc0
	 vfs_kern_mount.part.0+0x71/0xb0
	 btrfs_mount+0x10d/0x380
	 legacy_get_tree+0x30/0x50
	 vfs_get_tree+0x28/0xc0
	 path_mount+0x433/0xc10
	 __x64_sys_mount+0xe3/0x120
	 do_syscall_64+0x33/0x40
	 entry_SYSCALL_64_after_hwframe+0x44/0xa9

  -> #1 (sb_internal#2){.+.+}-{0:0}:
	 start_transaction+0x444/0x700
	 insert_balance_item.isra.0+0x37/0x320
	 btrfs_balance+0x354/0xf40
	 btrfs_ioctl_balance+0x2cf/0x380
	 __x64_sys_ioctl+0x83/0xb0
	 do_syscall_64+0x33/0x40
	 entry_SYSCALL_64_after_hwframe+0x44/0xa9

  -> #0 (&fs_info->balance_mutex){+.+.}-{3:3}:
	 __lock_acquire+0x1120/0x1e10
	 lock_acquire+0x116/0x370
	 __mutex_lock+0x7e/0x7b0
	 btrfs_recover_balance+0x2f0/0x340
	 open_ctree+0x1095/0x1726
	 btrfs_mount_root.cold+0x12/0xea
	 legacy_get_tree+0x30/0x50
	 vfs_get_tree+0x28/0xc0
	 vfs_kern_mount.part.0+0x71/0xb0
	 btrfs_mount+0x10d/0x380
	 legacy_get_tree+0x30/0x50
	 vfs_get_tree+0x28/0xc0
	 path_mount+0x433/0xc10
	 __x64_sys_mount+0xe3/0x120
	 do_syscall_64+0x33/0x40
	 entry_SYSCALL_64_after_hwframe+0x44/0xa9

  other info that might help us debug this:

  Chain exists of:
    &fs_info->balance_mutex --> sb_internal#2 --> btrfs-root-00

   Possible unsafe locking scenario:

	 CPU0                    CPU1
	 ----                    ----
    lock(btrfs-root-00);
				 lock(sb_internal#2);
				 lock(btrfs-root-00);
    lock(&fs_info->balance_mutex);

   *** DEADLOCK ***

  2 locks held by mount/779:
   #0: ffffa0e60dc040e0 (&type->s_umount_key#47/1){+.+.}-{3:3}, at: alloc_super+0xb5/0x380
   #1: ffffa0e60ee31da8 (btrfs-root-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x27/0x100

  stack backtrace:
  CPU: 0 PID: 779 Comm: mount Not tainted 5.10.0-rc6+ #217
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014
  Call Trace:
   dump_stack+0x8b/0xb0
   check_noncircular+0xcf/0xf0
   ? trace_call_bpf+0x139/0x260
   __lock_acquire+0x1120/0x1e10
   lock_acquire+0x116/0x370
   ? btrfs_recover_balance+0x2f0/0x340
   __mutex_lock+0x7e/0x7b0
   ? btrfs_recover_balance+0x2f0/0x340
   ? btrfs_recover_balance+0x2f0/0x340
   ? rcu_read_lock_sched_held+0x3f/0x80
   ? kmem_cache_alloc_trace+0x2c4/0x2f0
   ? btrfs_get_64+0x5e/0x100
   btrfs_recover_balance+0x2f0/0x340
   open_ctree+0x1095/0x1726
   btrfs_mount_root.cold+0x12/0xea
   ? rcu_read_lock_sched_held+0x3f/0x80
   legacy_get_tree+0x30/0x50
   vfs_get_tree+0x28/0xc0
   vfs_kern_mount.part.0+0x71/0xb0
   btrfs_mount+0x10d/0x380
   ? __kmalloc_track_caller+0x2f2/0x320
   legacy_get_tree+0x30/0x50
   vfs_get_tree+0x28/0xc0
   ? capable+0x3a/0x60
   path_mount+0x433/0xc10
   __x64_sys_mount+0xe3/0x120
   do_syscall_64+0x33/0x40
   entry_SYSCALL_64_after_hwframe+0x44/0xa9

This is straightforward to fix, simply release the path before we setup
the balance_ctl.

CC: [email protected] # 4.4+
Reviewed-by: Qu Wenruo <[email protected]>
Reviewed-by: Johannes Thumshirn <[email protected]>
Signed-off-by: Josef Bacik <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
Signed-off-by: William Breathitt Gray <[email protected]>
jwk404 pushed a commit to jwk404/linux-kernel-gcp that referenced this pull request Apr 1, 2021
delphix-devops-bot pushed a commit that referenced this pull request Apr 16, 2021
BugLink: https://bugs.launchpad.net/bugs/1916061

commit b25b0b8 upstream.

With the following patches:

- btrfs: backref, only collect file extent items matching backref offset
- btrfs: backref, not adding refs from shared block when resolving normal backref
- btrfs: backref, only search backref entries from leaves of the same root

we only collect the normal data refs we want, so the imprecise upper
bound total_refs of that EXTENT_ITEM could now be changed to the count
of the normal backref entry we want to search.

Background and how the patches fit together:

Btrfs has two types of data backref.
For BTRFS_EXTENT_DATA_REF_KEY type of backref, we don't have the
exact block number. Therefore, we need to call resolve_indirect_refs.
It uses btrfs_search_slot to locate the leaf block. Then
we need to walk through the leaves to search for the EXTENT_DATA items
that have disk bytenr matching the extent item (add_all_parents).

When resolving indirect refs, we could take entries that don't
belong to the backref entry we are searching for right now.
For that reason when searching backref entry, we always use total
refs of that EXTENT_ITEM rather than individual count.

For example:
item 11 key (40831553536 EXTENT_ITEM 4194304) itemoff 15460 itemsize
  extent refs 24 gen 7302 flags DATA
  shared data backref parent 394985472 count 10 #1
  extent data backref root 257 objectid 260 offset 1048576 count 3 #2
  extent data backref root 256 objectid 260 offset 65536 count 6 #3
  extent data backref root 257 objectid 260 offset 65536 count 5 #4

For example, when searching backref entry #4, we'll use total_refs
24, a very loose loop ending condition, instead of total_refs = 5.

But using total_refs = 24 is not accurate. Sometimes, we'll never find
all the refs from specific root.  As a result, the loop keeps on going
until we reach the end of that inode.

The first 3 patches, handle 3 different types refs we might encounter.
These refs do not belong to the normal backref we are searching, and
hence need to be skipped.

This patch changes the total_refs to correct number so that we could
end loop as soon as we find all the refs we want.

btrfs send uses backref to find possible clone sources, the following
is a simple test to compare the results with and without this patch:

 $ btrfs subvolume create /sub1
 $ for i in `seq 1 163840`; do
     dd if=/dev/zero of=/sub1/file bs=64K count=1 seek=$((i-1)) conv=notrunc oflag=direct
   done
 $ btrfs subvolume snapshot /sub1 /sub2
 $ for i in `seq 1 163840`; do
     dd if=/dev/zero of=/sub1/file bs=4K count=1 seek=$(((i-1)*16+10)) conv=notrunc oflag=direct
   done
 $ btrfs subvolume snapshot -r /sub1 /snap1
 $ time btrfs send /snap1 | btrfs receive /volume2

Without this patch:

real 69m48.124s
user 0m50.199s
sys  70m15.600s

With this patch:

real    1m59.683s
user    0m35.421s
sys     2m42.684s

Reviewed-by: Josef Bacik <[email protected]>
Reviewed-by: Johannes Thumshirn <[email protected]>
Signed-off-by: ethanwu <[email protected]>
[ add patchset cover letter with background and numbers ]
Signed-off-by: David Sterba <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
Signed-off-by: Stefan Bader <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request Apr 16, 2021
BugLink: https://bugs.launchpad.net/bugs/1918167

[ Upstream commit 3f618ab ]

When building with KASAN and LKDTM, clang may implictly generate an
asan.module_ctor function in the LKDTM rodata object. The Makefile moves
the lkdtm_rodata_do_nothing() function into .rodata by renaming the
file's .text section to .rodata, and consequently also moves the ctor
function into .rodata, leading to a boot time crash (splat below) when
the ctor is invoked by do_ctors().

Let's prevent this by marking the function as noinstr rather than
notrace, and renaming the file's .noinstr.text to .rodata. Marking the
function as noinstr will prevent tracing and kprobes, and will inhibit
any undesireable compiler instrumentation.

The ctor function (if any) will be placed in .text and will work
correctly.

Example splat before this patch is applied:

[    0.916359] Unable to handle kernel execute from non-executable memory at virtual address ffffa0006b60f5ac
[    0.922088] Mem abort info:
[    0.922828]   ESR = 0x8600000e
[    0.923635]   EC = 0x21: IABT (current EL), IL = 32 bits
[    0.925036]   SET = 0, FnV = 0
[    0.925838]   EA = 0, S1PTW = 0
[    0.926714] swapper pgtable: 4k pages, 48-bit VAs, pgdp=00000000427b3000
[    0.928489] [ffffa0006b60f5ac] pgd=000000023ffff003, p4d=000000023ffff003, pud=000000023fffe003, pmd=0068000042000f01
[    0.931330] Internal error: Oops: 8600000e [#1] PREEMPT SMP
[    0.932806] Modules linked in:
[    0.933617] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.10.0-rc7 #2
[    0.935620] Hardware name: linux,dummy-virt (DT)
[    0.936924] pstate: 40400005 (nZcv daif +PAN -UAO -TCO BTYPE=--)
[    0.938609] pc : asan.module_ctor+0x0/0x14
[    0.939759] lr : do_basic_setup+0x4c/0x70
[    0.940889] sp : ffff27b600177e30
[    0.941815] x29: ffff27b600177e30 x28: 0000000000000000
[    0.943306] x27: 0000000000000000 x26: 0000000000000000
[    0.944803] x25: 0000000000000000 x24: 0000000000000000
[    0.946289] x23: 0000000000000001 x22: 0000000000000000
[    0.947777] x21: ffffa0006bf4a890 x20: ffffa0006befb6c0
[    0.949271] x19: ffffa0006bef9358 x18: 0000000000000068
[    0.950756] x17: fffffffffffffff8 x16: 0000000000000000
[    0.952246] x15: 0000000000000000 x14: 0000000000000000
[    0.953734] x13: 00000000838a16d5 x12: 0000000000000001
[    0.955223] x11: ffff94000da74041 x10: dfffa00000000000
[    0.956715] x9 : 0000000000000000 x8 : ffffa0006b60f5ac
[    0.958199] x7 : f9f9f9f9f9f9f9f9 x6 : 000000000000003f
[    0.959683] x5 : 0000000000000040 x4 : 0000000000000000
[    0.961178] x3 : ffffa0006bdc15a0 x2 : 0000000000000005
[    0.962662] x1 : 00000000000000f9 x0 : ffffa0006bef9350
[    0.964155] Call trace:
[    0.964844]  asan.module_ctor+0x0/0x14
[    0.965895]  kernel_init_freeable+0x158/0x198
[    0.967115]  kernel_init+0x14/0x19c
[    0.968104]  ret_from_fork+0x10/0x30
[    0.969110] Code: 00000003 00000000 00000000 00000000 (00000000)
[    0.970815] ---[ end trace b5339784e20d015c ]---

Cc: Arnd Bergmann <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Kees Cook <[email protected]>
Acked-by: Kees Cook <[email protected]>
Signed-off-by: Mark Rutland <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
Signed-off-by: Kelsey Skunberg <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request May 12, 2021
BugLink: https://bugs.launchpad.net/bugs/1918974

[ Upstream commit eaba3b2 ]

Unprivileged user can crash kernel by using DRM_IOCTL_NOUVEAU_CHANNEL_ALLOC
ioctl. This was reported by trinity[1] fuzzer.

[   71.073906] nouveau 0000:01:00.0: crashme[1329]: channel failed to initialise, -17
[   71.081730] BUG: kernel NULL pointer dereference, address: 00000000000000a0
[   71.088928] #PF: supervisor read access in kernel mode
[   71.094059] #PF: error_code(0x0000) - not-present page
[   71.099189] PGD 119590067 P4D 119590067 PUD 1054f5067 PMD 0
[   71.104842] Oops: 0000 [#1] SMP NOPTI
[   71.108498] CPU: 2 PID: 1329 Comm: crashme Not tainted 5.8.0-rc6+ #2
[   71.114993] Hardware name: AMD Pike/Pike, BIOS RPK1506A 09/03/2014
[   71.121213] RIP: 0010:nouveau_abi16_ioctl_channel_alloc+0x108/0x380 [nouveau]
[   71.128339] Code: 48 89 9d f0 00 00 00 41 8b 4c 24 04 41 8b 14 24 45 31 c0 4c 8d 4b 10 48 89 ee 4c 89 f7 e8 10 11 00 00 85 c0 75 78 48 8b 43 10 <8b> 90 a0 00 00 00 41 89 54 24 08 80 7d 3d 05 0f 86 bb 01 00 00 41
[   71.147074] RSP: 0018:ffffb4a1809cfd38 EFLAGS: 00010246
[   71.152526] RAX: 0000000000000000 RBX: ffff98cedbaa1d20 RCX: 00000000000003bf
[   71.159651] RDX: 00000000000003be RSI: 0000000000000000 RDI: 0000000000030160
[   71.166774] RBP: ffff98cee776de00 R08: ffffdc0144198a08 R09: ffff98ceeefd4000
[   71.173901] R10: ffff98cee7e81780 R11: 0000000000000001 R12: ffffb4a1809cfe08
[   71.181214] R13: ffff98cee776d000 R14: ffff98cec519e000 R15: ffff98cee776def0
[   71.188339] FS:  00007fd926250500(0000) GS:ffff98ceeac80000(0000) knlGS:0000000000000000
[   71.196418] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   71.202155] CR2: 00000000000000a0 CR3: 0000000106622000 CR4: 00000000000406e0
[   71.209297] Call Trace:
[   71.211777]  ? nouveau_abi16_ioctl_getparam+0x1f0/0x1f0 [nouveau]
[   71.218053]  drm_ioctl_kernel+0xac/0xf0 [drm]
[   71.222421]  drm_ioctl+0x211/0x3c0 [drm]
[   71.226379]  ? nouveau_abi16_ioctl_getparam+0x1f0/0x1f0 [nouveau]
[   71.232500]  nouveau_drm_ioctl+0x57/0xb0 [nouveau]
[   71.237285]  ksys_ioctl+0x86/0xc0
[   71.240595]  __x64_sys_ioctl+0x16/0x20
[   71.244340]  do_syscall_64+0x4c/0x90
[   71.248110]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   71.253162] RIP: 0033:0x7fd925d4b88b
[   71.256731] Code: Bad RIP value.
[   71.259955] RSP: 002b:00007ffc743592d8 EFLAGS: 00000206 ORIG_RAX: 0000000000000010
[   71.267514] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd925d4b88b
[   71.274637] RDX: 0000000000601080 RSI: 00000000c0586442 RDI: 0000000000000003
[   71.281986] RBP: 00007ffc74359340 R08: 00007fd926016ce0 R09: 00007fd926016ce0
[   71.289111] R10: 0000000000000003 R11: 0000000000000206 R12: 0000000000400620
[   71.296235] R13: 00007ffc74359420 R14: 0000000000000000 R15: 0000000000000000
[   71.303361] Modules linked in: rfkill sunrpc snd_hda_codec_realtek snd_hda_codec_generic ledtrig_audio snd_hda_intel snd_intel_dspcfg snd_hda_codec snd_hda_core edac_mce_amd snd_hwdep kvm_amd snd_seq ccp snd_seq_device snd_pcm kvm snd_timer snd irqbypass soundcore sp5100_tco pcspkr crct10dif_pclmul crc32_pclmul ghash_clmulni_intel wmi_bmof joydev i2c_piix4 fam15h_power k10temp acpi_cpufreq ip_tables xfs libcrc32c sd_mod t10_pi sg nouveau video mxm_wmi i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm broadcom bcm_phy_lib ata_generic ahci drm e1000 crc32c_intel libahci serio_raw tg3 libata firewire_ohci firewire_core wmi crc_itu_t dm_mirror dm_region_hash dm_log dm_mod
[   71.365269] CR2: 00000000000000a0

simplified reproducer
---------------------------------8<----------------------------------------
/*
 * gcc -o crashme crashme.c
 * ./crashme /dev/dri/renderD128
 */

struct drm_nouveau_channel_alloc {
	uint32_t     fb_ctxdma_handle;
	uint32_t     tt_ctxdma_handle;

	int          channel;
	uint32_t     pushbuf_domains;

	/* Notifier memory */
	uint32_t     notifier_handle;

	/* DRM-enforced subchannel assignments */
	struct {
		uint32_t handle;
		uint32_t grclass;
	} subchan[8];
	uint32_t nr_subchan;
};

static struct drm_nouveau_channel_alloc channel;

int main(int argc, char *argv[]) {
	int fd;
	int rv;

	if (argc != 2)
		die("usage: %s <dev>", 0, argv[0]);

	if ((fd = open(argv[1], O_RDONLY)) == -1)
		die("open %s", errno, argv[1]);

	if (ioctl(fd, DRM_IOCTL_NOUVEAU_CHANNEL_ALLOC, &channel) == -1 &&
			errno == EACCES)
		die("ioctl %s", errno, argv[1]);

	close(fd);

	printf("PASS\n");

	return 0;
}
---------------------------------8<----------------------------------------

[1] https://github.com/kernelslacker/trinity

Fixes: eeaf06a ("drm/nouveau/svm: initial support for shared virtual memory")
Signed-off-by: Frantisek Hrbata <[email protected]>
Reviewed-by: Karol Herbst <[email protected]>
Signed-off-by: Ben Skeggs <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>

Signed-off-by: Kamal Mostafa <[email protected]>
Signed-off-by: Kelsey Skunberg <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request May 12, 2021
BugLink: https://bugs.launchpad.net/bugs/1918974

[ Upstream commit 661f385 ]

During connection setup, the application may choose to zero-size inbound
and outbound READ queues, as well as the Receive queue.  This patch fixes
handling of zero-sized queues, but not prevents it.

Kamal Heib says in an initial error report:

 When running the blktests over siw the following shift-out-of-bounds is
 reported, this is happening because the passed IRD or ORD from the ulp
 could be zero which will lead to unexpected behavior when calling
 roundup_pow_of_two(), fix that by blocking zero values of ORD or IRD.

   UBSAN: shift-out-of-bounds in ./include/linux/log2.h:57:13
   shift exponent 64 is too large for 64-bit type 'long unsigned int'
   CPU: 20 PID: 3957 Comm: kworker/u64:13 Tainted: G S     5.10.0-rc6 #2
   Hardware name: Dell Inc. PowerEdge R630/02C2CP, BIOS 2.1.5 04/11/2016
   Workqueue: iw_cm_wq cm_work_handler [iw_cm]
   Call Trace:
    dump_stack+0x99/0xcb
    ubsan_epilogue+0x5/0x40
    __ubsan_handle_shift_out_of_bounds.cold.11+0xb4/0xf3
    ? down_write+0x183/0x3d0
    siw_qp_modify.cold.8+0x2d/0x32 [siw]
    ? __local_bh_enable_ip+0xa5/0xf0
    siw_accept+0x906/0x1b60 [siw]
    ? xa_load+0x147/0x1f0
    ? siw_connect+0x17a0/0x17a0 [siw]
    ? lock_downgrade+0x700/0x700
    ? siw_get_base_qp+0x1c2/0x340 [siw]
    ? _raw_spin_unlock_irqrestore+0x39/0x40
    iw_cm_accept+0x1f4/0x430 [iw_cm]
    rdma_accept+0x3fa/0xb10 [rdma_cm]
    ? check_flush_dependency+0x410/0x410
    ? cma_rep_recv+0x570/0x570 [rdma_cm]
    nvmet_rdma_queue_connect+0x1a62/0x2680 [nvmet_rdma]
    ? nvmet_rdma_alloc_cmds+0xce0/0xce0 [nvmet_rdma]
    ? lock_release+0x56e/0xcc0
    ? lock_downgrade+0x700/0x700
    ? lock_downgrade+0x700/0x700
    ? __xa_alloc_cyclic+0xef/0x350
    ? __xa_alloc+0x2d0/0x2d0
    ? rdma_restrack_add+0xbe/0x2c0 [ib_core]
    ? __ww_mutex_die+0x190/0x190
    cma_cm_event_handler+0xf2/0x500 [rdma_cm]
    iw_conn_req_handler+0x910/0xcb0 [rdma_cm]
    ? _raw_spin_unlock_irqrestore+0x39/0x40
    ? trace_hardirqs_on+0x1c/0x150
    ? cma_ib_handler+0x8a0/0x8a0 [rdma_cm]
    ? __kasan_kmalloc.constprop.7+0xc1/0xd0
    cm_work_handler+0x121c/0x17a0 [iw_cm]
    ? iw_cm_reject+0x190/0x190 [iw_cm]
    ? trace_hardirqs_on+0x1c/0x150
    process_one_work+0x8fb/0x16c0
    ? pwq_dec_nr_in_flight+0x320/0x320
    worker_thread+0x87/0xb40
    ? __kthread_parkme+0xd1/0x1a0
    ? process_one_work+0x16c0/0x16c0
    kthread+0x35f/0x430
    ? kthread_mod_delayed_work+0x180/0x180
    ret_from_fork+0x22/0x30

Fixes: a531975 ("rdma/siw: main include file")
Fixes: f29dd55 ("rdma/siw: queue pair methods")
Fixes: 8b6a361 ("rdma/siw: receive path")
Fixes: b9be6f1 ("rdma/siw: transmit path")
Fixes: 303ae1c ("rdma/siw: application interface")
Link: https://lore.kernel.org/r/[email protected]
Reported-by: Kamal Heib <[email protected]>
Reported-by: Yi Zhang <[email protected]>
Reported-by: kernel test robot <[email protected]>
Signed-off-by: Bernard Metzler <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
Signed-off-by: Kelsey Skunberg <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request May 12, 2021
BugLink: https://bugs.launchpad.net/bugs/1918974

[ Upstream commit 429fa96 ]

The size of tx_valid_cpus was calculated under the assumption that the
numa nodes identifiers are continuous, which is not the case in all archs
as this could lead to the following panic when trying to access an invalid
tx_valid_cpus index, avoid the following panic by using nr_node_ids
instead of num_online_nodes() to allocate the tx_valid_cpus size.

   Kernel attempted to read user page (8) - exploit attempt? (uid: 0)
   BUG: Kernel NULL pointer dereference on read at 0x00000008
   Faulting instruction address: 0xc0080000081b4a90
   Oops: Kernel access of bad area, sig: 11 [#1]
   LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA PowerNV
   Modules linked in: siw(+) rfkill rpcrdma ib_isert iscsi_target_mod ib_iser libiscsi scsi_transport_iscsi ib_srpt target_core_mod ib_srp scsi_transport_srp ib_ipoib rdma_ucm sunrpc ib_umad rdma_cm ib_cm iw_cm i40iw ib_uverbs ib_core i40e ses enclosure scsi_transport_sas ipmi_powernv ibmpowernv at24 ofpart ipmi_devintf regmap_i2c ipmi_msghandler powernv_flash uio_pdrv_genirq uio mtd opal_prd zram ip_tables xfs libcrc32c sd_mod t10_pi ast i2c_algo_bit drm_vram_helper drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec drm_ttm_helper ttm drm vmx_crypto aacraid drm_panel_orientation_quirks dm_mod
   CPU: 40 PID: 3279 Comm: modprobe Tainted: G        W      X --------- ---  5.11.0-0.rc4.129.eln108.ppc64le #2
   NIP:  c0080000081b4a90 LR: c0080000081b4a2c CTR: c0000000007ce1c0
   REGS: c000000027fa77b0 TRAP: 0300   Tainted: G        W      X --------- ---   (5.11.0-0.rc4.129.eln108.ppc64le)
   MSR:  9000000002009033 <SF,HV,VEC,EE,ME,IR,DR,RI,LE>  CR: 44224882  XER: 00000000
   CFAR: c0000000007ce200 DAR: 0000000000000008 DSISR: 40000000 IRQMASK: 0
   GPR00: c0080000081b4a2c c000000027fa7a50 c0080000081c3900 0000000000000040
   GPR04: c000000002023080 c000000012e1c300 000020072ad70000 0000000000000001
   GPR08: c000000001726068 0000000000000008 0000000000000008 c0080000081b5758
   GPR12: c0000000007ce1c0 c0000007fffc3000 00000001590b1e40 0000000000000000
   GPR16: 0000000000000000 0000000000000001 000000011ad68fc8 00007fffcc09c5c8
   GPR20: 0000000000000008 0000000000000000 00000001590b2850 00000001590b1d30
   GPR24: 0000000000043d68 000000011ad67a80 000000011ad67a80 0000000000100000
   GPR28: c000000012e1c300 c0000000020271c8 0000000000000001 c0080000081bf608
   NIP [c0080000081b4a90] siw_init_cpulist+0x194/0x214 [siw]
   LR [c0080000081b4a2c] siw_init_cpulist+0x130/0x214 [siw]
   Call Trace:
   [c000000027fa7a50] [c0080000081b4a2c] siw_init_cpulist+0x130/0x214 [siw] (unreliable)
   [c000000027fa7a90] [c0080000081b4e68] siw_init_module+0x40/0x2a0 [siw]
   [c000000027fa7b30] [c0000000000124f4] do_one_initcall+0x84/0x2e0
   [c000000027fa7c00] [c000000000267ffc] do_init_module+0x7c/0x350
   [c000000027fa7c90] [c00000000026a180] __do_sys_init_module+0x210/0x250
   [c000000027fa7db0] [c0000000000387e4] system_call_exception+0x134/0x230
   [c000000027fa7e10] [c00000000000d660] system_call_common+0xf0/0x27c
   Instruction dump:
   40810044 3d420000 e8bf0000 e88a82d0 3d420000 e90a82c8 792a1f24 7cc4302a
   7d2642aa 79291f24 7d25482a 7d295214 <7d4048a8> 7d4a3b78 7d4049ad 40c2fff4

Fixes: bdcf26b ("rdma/siw: network and RDMA core interface")
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Kamal Heib <[email protected]>
Reviewed-by: Bernard Metzler <[email protected]>
Tested-by: Yi Zhang <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
Signed-off-by: Kelsey Skunberg <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request May 12, 2021
BugLink: https://bugs.launchpad.net/bugs/1918974

[ Upstream commit c5c97ca ]

The ubsan reported the following error.  It was because sample's raw
data missed u32 padding at the end.  So it broke the alignment of the
array after it.

The raw data contains an u32 size prefix so the data size should have
an u32 padding after 8-byte aligned data.

27: Sample parsing  :util/synthetic-events.c:1539:4:
  runtime error: store to misaligned address 0x62100006b9bc for type
  '__u64' (aka 'unsigned long long'), which requires 8 byte alignment
0x62100006b9bc: note: pointer points here
  00 00 00 00 ff ff ff ff  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
              ^
    #0 0x561532a9fc96 in perf_event__synthesize_sample util/synthetic-events.c:1539:13
    #1 0x5615327f4a4f in do_test tests/sample-parsing.c:284:8
    #2 0x5615327f3f50 in test__sample_parsing tests/sample-parsing.c:381:9
    #3 0x56153279d3a1 in run_test tests/builtin-test.c:424:9
    #4 0x56153279c836 in test_and_print tests/builtin-test.c:454:9
    #5 0x56153279b7eb in __cmd_test tests/builtin-test.c:675:4
    #6 0x56153279abf0 in cmd_test tests/builtin-test.c:821:9
    #7 0x56153264e796 in run_builtin perf.c:312:11
    #8 0x56153264cf03 in handle_internal_command perf.c:364:8
    #9 0x56153264e47d in run_argv perf.c:408:2
    #10 0x56153264c9a9 in main perf.c:538:3
    #11 0x7f137ab6fbbc in __libc_start_main (/lib64/libc.so.6+0x38bbc)
    #12 0x561532596828 in _start ...

SUMMARY: UndefinedBehaviorSanitizer: misaligned-pointer-use
 util/synthetic-events.c:1539:4 in

Fixes: 045f8cd ("perf tests: Add a sample parsing test")
Signed-off-by: Namhyung Kim <[email protected]>
Acked-by: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
Signed-off-by: Kelsey Skunberg <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request Jun 6, 2021
BugLink: https://bugs.launchpad.net/bugs/1923214

commit a7889c6 upstream.

afs_listxattr() lists all the available special afs xattrs (i.e. those in
the "afs.*" space), no matter what type of server we're dealing with.  But
OpenAFS servers, for example, cannot deal with some of the extra-capable
attributes that AuriStor (YFS) servers provide.  Unfortunately, the
presence of the afs.yfs.* attributes causes errors[1] for anything that
tries to read them if the server is of the wrong type.

Fix the problem by removing afs_listxattr() so that none of the special
xattrs are listed (AFS doesn't support xattrs).  It does mean, however,
that getfattr won't list them, though they can still be accessed with
getxattr() and setxattr().

This can be tested with something like:

	getfattr -d -m ".*" /afs/example.com/path/to/file

With this change, none of the afs.* attributes should be visible.

Changes:
ver #2:
 - Hide all of the afs.* xattrs, not just the ACL ones.

Fixes: ae46578 ("afs: Get YFS ACLs and information through xattrs")
Reported-by: Gaja Sophie Peters <[email protected]>
Signed-off-by: David Howells <[email protected]>
Tested-by: Gaja Sophie Peters <[email protected]>
Reviewed-by: Jeffrey Altman <[email protected]>
Reviewed-by: Marc Dionne <[email protected]>
cc: [email protected]
Link: http://lists.infradead.org/pipermail/linux-afs/2021-March/003502.html [1]
Link: http://lists.infradead.org/pipermail/linux-afs/2021-March/003567.html # v1
Link: http://lists.infradead.org/pipermail/linux-afs/2021-March/003573.html # v2
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
Signed-off-by: Stefan Bader <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request Jun 6, 2021
BugLink: https://bugs.launchpad.net/bugs/1923214

commit c7de87f upstream.

[ This problem is in mainline, but only rt has the chops to be
able to detect it. ]

Lockdep reports a circular lock dependency between serv->sv_lock and
softirq_ctl.lock on system shutdown, when using a kernel built with
CONFIG_PREEMPT_RT=y, and a nfs mount exists.

This is due to the definition of spin_lock_bh on rt:

	local_bh_disable();
	rt_spin_lock(lock);

which forces a softirq_ctl.lock -> serv->sv_lock dependency.  This is
not a problem as long as _every_ lock of serv->sv_lock is a:

	spin_lock_bh(&serv->sv_lock);

but there is one of the form:

	spin_lock(&serv->sv_lock);

This is what is causing the circular dependency splat.  The spin_lock()
grabs the lock without first grabbing softirq_ctl.lock via local_bh_disable.
If later on in the critical region,  someone does a local_bh_disable, we
get a serv->sv_lock -> softirq_ctrl.lock dependency established.  Deadlock.

Fix is to make serv->sv_lock be locked with spin_lock_bh everywhere, no
exceptions.

[  OK  ] Stopped target NFS client services.
         Stopping Logout off all iSCSI sessions on shutdown...
         Stopping NFS server and services...
[  109.442380]
[  109.442385] ======================================================
[  109.442386] WARNING: possible circular locking dependency detected
[  109.442387] 5.10.16-rt30 #1 Not tainted
[  109.442389] ------------------------------------------------------
[  109.442390] nfsd/1032 is trying to acquire lock:
[  109.442392] ffff994237617f60 ((softirq_ctrl.lock).lock){+.+.}-{2:2}, at: __local_bh_disable_ip+0xd9/0x270
[  109.442405]
[  109.442405] but task is already holding lock:
[  109.442406] ffff994245cb00b0 (&serv->sv_lock){+.+.}-{0:0}, at: svc_close_list+0x1f/0x90
[  109.442415]
[  109.442415] which lock already depends on the new lock.
[  109.442415]
[  109.442416]
[  109.442416] the existing dependency chain (in reverse order) is:
[  109.442417]
[  109.442417] -> #1 (&serv->sv_lock){+.+.}-{0:0}:
[  109.442421]        rt_spin_lock+0x2b/0xc0
[  109.442428]        svc_add_new_perm_xprt+0x42/0xa0
[  109.442430]        svc_addsock+0x135/0x220
[  109.442434]        write_ports+0x4b3/0x620
[  109.442438]        nfsctl_transaction_write+0x45/0x80
[  109.442440]        vfs_write+0xff/0x420
[  109.442444]        ksys_write+0x4f/0xc0
[  109.442446]        do_syscall_64+0x33/0x40
[  109.442450]        entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  109.442454]
[  109.442454] -> #0 ((softirq_ctrl.lock).lock){+.+.}-{2:2}:
[  109.442457]        __lock_acquire+0x1264/0x20b0
[  109.442463]        lock_acquire+0xc2/0x400
[  109.442466]        rt_spin_lock+0x2b/0xc0
[  109.442469]        __local_bh_disable_ip+0xd9/0x270
[  109.442471]        svc_xprt_do_enqueue+0xc0/0x4d0
[  109.442474]        svc_close_list+0x60/0x90
[  109.442476]        svc_close_net+0x49/0x1a0
[  109.442478]        svc_shutdown_net+0x12/0x40
[  109.442480]        nfsd_destroy+0xc5/0x180
[  109.442482]        nfsd+0x1bc/0x270
[  109.442483]        kthread+0x194/0x1b0
[  109.442487]        ret_from_fork+0x22/0x30
[  109.442492]
[  109.442492] other info that might help us debug this:
[  109.442492]
[  109.442493]  Possible unsafe locking scenario:
[  109.442493]
[  109.442493]        CPU0                    CPU1
[  109.442494]        ----                    ----
[  109.442495]   lock(&serv->sv_lock);
[  109.442496]                                lock((softirq_ctrl.lock).lock);
[  109.442498]                                lock(&serv->sv_lock);
[  109.442499]   lock((softirq_ctrl.lock).lock);
[  109.442501]
[  109.442501]  *** DEADLOCK ***
[  109.442501]
[  109.442501] 3 locks held by nfsd/1032:
[  109.442503]  #0: ffffffff93b49258 (nfsd_mutex){+.+.}-{3:3}, at: nfsd+0x19a/0x270
[  109.442508]  #1: ffff994245cb00b0 (&serv->sv_lock){+.+.}-{0:0}, at: svc_close_list+0x1f/0x90
[  109.442512]  #2: ffffffff93a81b20 (rcu_read_lock){....}-{1:2}, at: rt_spin_lock+0x5/0xc0
[  109.442518]
[  109.442518] stack backtrace:
[  109.442519] CPU: 0 PID: 1032 Comm: nfsd Not tainted 5.10.16-rt30 #1
[  109.442522] Hardware name: Supermicro X9DRL-3F/iF/X9DRL-3F/iF, BIOS 3.2 09/22/2015
[  109.442524] Call Trace:
[  109.442527]  dump_stack+0x77/0x97
[  109.442533]  check_noncircular+0xdc/0xf0
[  109.442546]  __lock_acquire+0x1264/0x20b0
[  109.442553]  lock_acquire+0xc2/0x400
[  109.442564]  rt_spin_lock+0x2b/0xc0
[  109.442570]  __local_bh_disable_ip+0xd9/0x270
[  109.442573]  svc_xprt_do_enqueue+0xc0/0x4d0
[  109.442577]  svc_close_list+0x60/0x90
[  109.442581]  svc_close_net+0x49/0x1a0
[  109.442585]  svc_shutdown_net+0x12/0x40
[  109.442588]  nfsd_destroy+0xc5/0x180
[  109.442590]  nfsd+0x1bc/0x270
[  109.442595]  kthread+0x194/0x1b0
[  109.442600]  ret_from_fork+0x22/0x30
[  109.518225] nfsd: last server has exited, flushing export cache
[  OK  ] Stopped NFSv4 ID-name mapping service.
[  OK  ] Stopped GSSAPI Proxy Daemon.
[  OK  ] Stopped NFS Mount Daemon.
[  OK  ] Stopped NFS status monitor for NFSv2/3 locking..

Fixes: 719f8bc ("svcrpc: fix xpt_list traversal locking on shutdown")
Signed-off-by: Joe Korty <[email protected]>
Signed-off-by: Chuck Lever <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
Signed-off-by: Stefan Bader <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request Jun 6, 2021
BugLink: https://bugs.launchpad.net/bugs/1923220

[ Upstream commit 4deb550 ]

label err_eni_release is reachable when eni_start() fail.
In eni_start() it calls dev->phy->start() in the last step, if start()
fail we don't need to call phy->stop(), if start() is never called, we
neither need to call phy->stop(), otherwise null-ptr-deref will happen.

In order to fix this issue, don't call phy->stop() in label err_eni_release

[    4.875714] ==================================================================
[    4.876091] BUG: KASAN: null-ptr-deref in suni_stop+0x47/0x100 [suni]
[    4.876433] Read of size 8 at addr 0000000000000030 by task modprobe/95
[    4.876778]
[    4.876862] CPU: 0 PID: 95 Comm: modprobe Not tainted 5.11.0-rc7-00090-gdcc0b49040c7 #2
[    4.877290] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-48-gd94
[    4.877876] Call Trace:
[    4.878009]  dump_stack+0x7d/0xa3
[    4.878191]  kasan_report.cold+0x10c/0x10e
[    4.878410]  ? __slab_free+0x2f0/0x340
[    4.878612]  ? suni_stop+0x47/0x100 [suni]
[    4.878832]  suni_stop+0x47/0x100 [suni]
[    4.879043]  eni_do_release+0x3b/0x70 [eni]
[    4.879269]  eni_init_one.cold+0x1152/0x1747 [eni]
[    4.879528]  ? _raw_spin_lock_irqsave+0x7b/0xd0
[    4.879768]  ? eni_ioctl+0x270/0x270 [eni]
[    4.879990]  ? __mutex_lock_slowpath+0x10/0x10
[    4.880226]  ? eni_ioctl+0x270/0x270 [eni]
[    4.880448]  local_pci_probe+0x6f/0xb0
[    4.880650]  pci_device_probe+0x171/0x240
[    4.880864]  ? pci_device_remove+0xe0/0xe0
[    4.881086]  ? kernfs_create_link+0xb6/0x110
[    4.881315]  ? sysfs_do_create_link_sd.isra.0+0x76/0xe0
[    4.881594]  really_probe+0x161/0x420
[    4.881791]  driver_probe_device+0x6d/0xd0
[    4.882010]  device_driver_attach+0x82/0x90
[    4.882233]  ? device_driver_attach+0x90/0x90
[    4.882465]  __driver_attach+0x60/0x100
[    4.882671]  ? device_driver_attach+0x90/0x90
[    4.882903]  bus_for_each_dev+0xe1/0x140
[    4.883114]  ? subsys_dev_iter_exit+0x10/0x10
[    4.883346]  ? klist_node_init+0x61/0x80
[    4.883557]  bus_add_driver+0x254/0x2a0
[    4.883764]  driver_register+0xd3/0x150
[    4.883971]  ? 0xffffffffc0038000
[    4.884149]  do_one_initcall+0x84/0x250
[    4.884355]  ? trace_event_raw_event_initcall_finish+0x150/0x150
[    4.884674]  ? unpoison_range+0xf/0x30
[    4.884875]  ? ____kasan_kmalloc.constprop.0+0x84/0xa0
[    4.885150]  ? unpoison_range+0xf/0x30
[    4.885352]  ? unpoison_range+0xf/0x30
[    4.885557]  do_init_module+0xf8/0x350
[    4.885760]  load_module+0x3fe6/0x4340
[    4.885960]  ? vm_unmap_ram+0x1d0/0x1d0
[    4.886166]  ? ____kasan_kmalloc.constprop.0+0x84/0xa0
[    4.886441]  ? module_frob_arch_sections+0x20/0x20
[    4.886697]  ? __do_sys_finit_module+0x108/0x170
[    4.886941]  __do_sys_finit_module+0x108/0x170
[    4.887178]  ? __ia32_sys_init_module+0x40/0x40
[    4.887419]  ? file_open_root+0x200/0x200
[    4.887634]  ? do_sys_open+0x85/0xe0
[    4.887826]  ? filp_open+0x50/0x50
[    4.888009]  ? fpregs_assert_state_consistent+0x4d/0x60
[    4.888287]  ? exit_to_user_mode_prepare+0x2f/0x130
[    4.888547]  do_syscall_64+0x33/0x40
[    4.888739]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[    4.889010] RIP: 0033:0x7ff62fcf1cf7
[    4.889202] Code: 48 89 57 30 48 8b 04 24 48 89 47 38 e9 1d a0 02 00 48 89 f8 48 89 f71
[    4.890172] RSP: 002b:00007ffe6644ade8 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
[    4.890570] RAX: ffffffffffffffda RBX: 0000000000f2ca70 RCX: 00007ff62fcf1cf7
[    4.890944] RDX: 0000000000000000 RSI: 0000000000f2b9e0 RDI: 0000000000000003
[    4.891318] RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000001
[    4.891691] R10: 00007ff62fd55300 R11: 0000000000000246 R12: 0000000000f2b9e0
[    4.892064] R13: 0000000000000000 R14: 0000000000f2bdd0 R15: 0000000000000001
[    4.892439] ==================================================================

Signed-off-by: Tong Zhang <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
Signed-off-by: Stefan Bader <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request Jun 6, 2021
BugLink: https://bugs.launchpad.net/bugs/1926489

commit 90bd070 upstream.

The following deadlock is detected:

  truncate -> setattr path is waiting for pending direct IO to be done (inode->i_dio_count become zero) with inode->i_rwsem held (down_write).

  PID: 14827  TASK: ffff881686a9af80  CPU: 20  COMMAND: "ora_p005_hrltd9"
   #0  __schedule at ffffffff818667cc
   #1  schedule at ffffffff81866de6
   #2  inode_dio_wait at ffffffff812a2d04
   #3  ocfs2_setattr at ffffffffc05f322e [ocfs2]
   #4  notify_change at ffffffff812a5a09
   #5  do_truncate at ffffffff812808f5
   #6  do_sys_ftruncate.constprop.18 at ffffffff81280cf2
   #7  sys_ftruncate at ffffffff81280d8e
   #8  do_syscall_64 at ffffffff81003949
   #9  entry_SYSCALL_64_after_hwframe at ffffffff81a001ad

dio completion path is going to complete one direct IO (decrement
inode->i_dio_count), but before that it hung at locking inode->i_rwsem:

   #0  __schedule+700 at ffffffff818667cc
   #1  schedule+54 at ffffffff81866de6
   #2  rwsem_down_write_failed+536 at ffffffff8186aa28
   #3  call_rwsem_down_write_failed+23 at ffffffff8185a1b7
   #4  down_write+45 at ffffffff81869c9d
   #5  ocfs2_dio_end_io_write+180 at ffffffffc05d5444 [ocfs2]
   #6  ocfs2_dio_end_io+85 at ffffffffc05d5a85 [ocfs2]
   #7  dio_complete+140 at ffffffff812c873c
   #8  dio_aio_complete_work+25 at ffffffff812c89f9
   #9  process_one_work+361 at ffffffff810b1889
  #10  worker_thread+77 at ffffffff810b233d
  #11  kthread+261 at ffffffff810b7fd5
  #12  ret_from_fork+62 at ffffffff81a0035e

Thus above forms ABBA deadlock.  The same deadlock was mentioned in
upstream commit 28f5a8a ("ocfs2: should wait dio before inode lock
in ocfs2_setattr()").  It seems that that commit only removed the
cluster lock (the victim of above dead lock) from the ABBA deadlock
party.

End-user visible effects: Process hang in truncate -> ocfs2_setattr path
and other processes hang at ocfs2_dio_end_io_write path.

This is to fix the deadlock itself.  It removes inode_lock() call from
dio completion path to remove the deadlock and add ip_alloc_sem lock in
setattr path to synchronize the inode modifications.

[[email protected]: remove the "had_alloc_lock" as suggested]
  Link: https://lkml.kernel.org/r/[email protected]

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Wengang Wang <[email protected]>
Reviewed-by: Joseph Qi <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Junxiao Bi <[email protected]>
Cc: Changwei Ge <[email protected]>
Cc: Gang He <[email protected]>
Cc: Jun Piao <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
Signed-off-by: Stefan Bader <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request Sep 25, 2025
BugLink: https://bugs.launchpad.net/bugs/2115678

[ Upstream commit 1b9366c601039d60546794c63fbb83ce8e53b978 ]

If waiting for gpu reset done in KFD release_work, thers is WARNING:
possible circular locking dependency detected

  #2  kfd_create_process
        kfd_process_mutex
          flush kfd release work

  #1  kfd release work
        wait for amdgpu reset work

  #0  amdgpu_device_gpu_reset
        kgd2kfd_pre_reset
          kfd_process_mutex

  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock((work_completion)(&p->release_work));
                  lock((wq_completion)kfd_process_wq);
                  lock((work_completion)(&p->release_work));
   lock((wq_completion)amdgpu-reset-dev);

To fix this, KFD create process move flush release work outside
kfd_process_mutex.

Signed-off-by: Philip Yang <[email protected]>
Reviewed-by: Felix Kuehling <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: Manuel Diewald <[email protected]>
Signed-off-by: Mehmet Basaran <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request Sep 25, 2025
BugLink: https://bugs.launchpad.net/bugs/2115678

[ Upstream commit 88f7f56d16f568f19e1a695af34a7f4a6ce537a6 ]

When a bio with REQ_PREFLUSH is submitted to dm, __send_empty_flush()
generates a flush_bio with REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC,
which causes the flush_bio to be throttled by wbt_wait().

An example from v5.4, similar problem also exists in upstream:

    crash> bt 2091206
    PID: 2091206  TASK: ffff2050df92a300  CPU: 109  COMMAND: "kworker/u260:0"
     #0 [ffff800084a2f7f0] __switch_to at ffff80004008aeb8
     #1 [ffff800084a2f820] __schedule at ffff800040bfa0c4
     #2 [ffff800084a2f880] schedule at ffff800040bfa4b4
     #3 [ffff800084a2f8a0] io_schedule at ffff800040bfa9c4
     #4 [ffff800084a2f8c0] rq_qos_wait at ffff8000405925bc
     #5 [ffff800084a2f940] wbt_wait at ffff8000405bb3a0
     #6 [ffff800084a2f9a0] __rq_qos_throttle at ffff800040592254
     #7 [ffff800084a2f9c0] blk_mq_make_request at ffff80004057cf38
     #8 [ffff800084a2fa60] generic_make_request at ffff800040570138
     #9 [ffff800084a2fae0] submit_bio at ffff8000405703b4
    #10 [ffff800084a2fb50] xlog_write_iclog at ffff800001280834 [xfs]
    #11 [ffff800084a2fbb0] xlog_sync at ffff800001280c3c [xfs]
    #12 [ffff800084a2fbf0] xlog_state_release_iclog at ffff800001280df4 [xfs]
    #13 [ffff800084a2fc10] xlog_write at ffff80000128203c [xfs]
    #14 [ffff800084a2fcd0] xlog_cil_push at ffff8000012846dc [xfs]
    #15 [ffff800084a2fda0] xlog_cil_push_work at ffff800001284a2c [xfs]
    #16 [ffff800084a2fdb0] process_one_work at ffff800040111d08
    #17 [ffff800084a2fe00] worker_thread at ffff8000401121cc
    #18 [ffff800084a2fe70] kthread at ffff800040118de4

After commit 2def284 ("xfs: don't allow log IO to be throttled"),
the metadata submitted by xlog_write_iclog() should not be throttled.
But due to the existence of the dm layer, throttling flush_bio indirectly
causes the metadata bio to be throttled.

Fix this by conditionally adding REQ_IDLE to flush_bio.bi_opf, which makes
wbt_should_throttle() return false to avoid wbt_wait().

Signed-off-by: Jinliang Zheng <[email protected]>
Reviewed-by: Tianxiang Peng <[email protected]>
Reviewed-by: Hao Peng <[email protected]>
Signed-off-by: Mikulas Patocka <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
CVE-2025-38063
Signed-off-by: Manuel Diewald <[email protected]>
Signed-off-by: Mehmet Basaran <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request Sep 25, 2025
BugLink: https://bugs.launchpad.net/bugs/2119603

[ Upstream commit ee684de5c1b0ac01821320826baec7da93f3615b ]

As shown in [1], it is possible to corrupt a BPF ELF file such that
arbitrary BPF instructions are loaded by libbpf. This can be done by
setting a symbol (BPF program) section offset to a large (unsigned)
number such that <section start + symbol offset> overflows and points
before the section data in the memory.

Consider the situation below where:
- prog_start = sec_start + symbol_offset    <-- size_t overflow here
- prog_end   = prog_start + prog_size

    prog_start        sec_start        prog_end        sec_end
        |                |                 |              |
        v                v                 v              v
    .....................|################################|............

The report in [1] also provides a corrupted BPF ELF which can be used as
a reproducer:

    $ readelf -S crash
    Section Headers:
      [Nr] Name              Type             Address           Offset
           Size              EntSize          Flags  Link  Info  Align
    ...
      [ 2] uretprobe.mu[...] PROGBITS         0000000000000000  00000040
           0000000000000068  0000000000000000  AX       0     0     8

    $ readelf -s crash
    Symbol table '.symtab' contains 8 entries:
       Num:    Value          Size Type    Bind   Vis      Ndx Name
    ...
         6: ffffffffffffffb8   104 FUNC    GLOBAL DEFAULT    2 handle_tp

Here, the handle_tp prog has section offset ffffffffffffffb8, i.e. will
point before the actual memory where section 2 is allocated.

This is also reported by AddressSanitizer:

    =================================================================
    ==1232==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x7c7302fe0000 at pc 0x7fc3046e4b77 bp 0x7ffe64677cd0 sp 0x7ffe64677490
    READ of size 104 at 0x7c7302fe0000 thread T0
        #0 0x7fc3046e4b76 in memcpy (/lib64/libasan.so.8+0xe4b76)
        #1 0x00000040df3e in bpf_object__init_prog /src/libbpf/src/libbpf.c:856
        #2 0x00000040df3e in bpf_object__add_programs /src/libbpf/src/libbpf.c:928
        #3 0x00000040df3e in bpf_object__elf_collect /src/libbpf/src/libbpf.c:3930
        #4 0x00000040df3e in bpf_object_open /src/libbpf/src/libbpf.c:8067
        #5 0x00000040f176 in bpf_object__open_file /src/libbpf/src/libbpf.c:8090
        #6 0x000000400c16 in main /poc/poc.c:8
        #7 0x7fc3043d25b4 in __libc_start_call_main (/lib64/libc.so.6+0x35b4)
        #8 0x7fc3043d2667 in __libc_start_main@@GLIBC_2.34 (/lib64/libc.so.6+0x3667)
        #9 0x000000400b34 in _start (/poc/poc+0x400b34)

    0x7c7302fe0000 is located 64 bytes before 104-byte region [0x7c7302fe0040,0x7c7302fe00a8)
    allocated by thread T0 here:
        #0 0x7fc3046e716b in malloc (/lib64/libasan.so.8+0xe716b)
        #1 0x7fc3045ee600 in __libelf_set_rawdata_wrlock (/lib64/libelf.so.1+0xb600)
        #2 0x7fc3045ef018 in __elf_getdata_rdlock (/lib64/libelf.so.1+0xc018)
        #3 0x00000040642f in elf_sec_data /src/libbpf/src/libbpf.c:3740

The problem here is that currently, libbpf only checks that the program
end is within the section bounds. There used to be a check
`while (sec_off < sec_sz)` in bpf_object__add_programs, however, it was
removed by commit 6245947 ("libbpf: Allow gaps in BPF program
sections to support overriden weak functions").

Add a check for detecting the overflow of `sec_off + prog_sz` to
bpf_object__init_prog to fix this issue.

[1] https://github.com/lmarch2/poc/blob/main/libbpf/libbpf.md

Fixes: 6245947 ("libbpf: Allow gaps in BPF program sections to support overriden weak functions")
Reported-by: lmarch2 <[email protected]>
Signed-off-by: Viktor Malik <[email protected]>
Signed-off-by: Andrii Nakryiko <[email protected]>
Reviewed-by: Shung-Hsi Yu <[email protected]>
Link: https://github.com/lmarch2/poc/blob/main/libbpf/libbpf.md
Link: https://lore.kernel.org/bpf/[email protected]
Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: Manuel Diewald <[email protected]>
Signed-off-by: Mehmet Basaran <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request Sep 25, 2025
BugLink: https://bugs.launchpad.net/bugs/2119603

commit c98cc9797b7009308fff73d41bc1d08642dab77a upstream.

Running a modified trace-cmd record --nosplice where it does a mmap of the
ring buffer when '--nosplice' is set, caused the following lockdep splat:

 ======================================================
 WARNING: possible circular locking dependency detected
 6.15.0-rc7-test-00002-gfb7d03d8a82f #551 Not tainted
 ------------------------------------------------------
 trace-cmd/1113 is trying to acquire lock:
 ffff888100062888 (&buffer->mutex){+.+.}-{4:4}, at: ring_buffer_map+0x11c/0xe70

 but task is already holding lock:
 ffff888100a5f9f8 (&cpu_buffer->mapping_lock){+.+.}-{4:4}, at: ring_buffer_map+0xcf/0xe70

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #5 (&cpu_buffer->mapping_lock){+.+.}-{4:4}:
        __mutex_lock+0x192/0x18c0
        ring_buffer_map+0xcf/0xe70
        tracing_buffers_mmap+0x1c4/0x3b0
        __mmap_region+0xd8d/0x1f70
        do_mmap+0x9d7/0x1010
        vm_mmap_pgoff+0x20b/0x390
        ksys_mmap_pgoff+0x2e9/0x440
        do_syscall_64+0x79/0x1c0
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 -> #4 (&mm->mmap_lock){++++}-{4:4}:
        __might_fault+0xa5/0x110
        _copy_to_user+0x22/0x80
        _perf_ioctl+0x61b/0x1b70
        perf_ioctl+0x62/0x90
        __x64_sys_ioctl+0x134/0x190
        do_syscall_64+0x79/0x1c0
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 -> #3 (&cpuctx_mutex){+.+.}-{4:4}:
        __mutex_lock+0x192/0x18c0
        perf_event_init_cpu+0x325/0x7c0
        perf_event_init+0x52a/0x5b0
        start_kernel+0x263/0x3e0
        x86_64_start_reservations+0x24/0x30
        x86_64_start_kernel+0x95/0xa0
        common_startup_64+0x13e/0x141

 -> #2 (pmus_lock){+.+.}-{4:4}:
        __mutex_lock+0x192/0x18c0
        perf_event_init_cpu+0xb7/0x7c0
        cpuhp_invoke_callback+0x2c0/0x1030
        __cpuhp_invoke_callback_range+0xbf/0x1f0
        _cpu_up+0x2e7/0x690
        cpu_up+0x117/0x170
        cpuhp_bringup_mask+0xd5/0x120
        bringup_nonboot_cpus+0x13d/0x170
        smp_init+0x2b/0xf0
        kernel_init_freeable+0x441/0x6d0
        kernel_init+0x1e/0x160
        ret_from_fork+0x34/0x70
        ret_from_fork_asm+0x1a/0x30

 -> #1 (cpu_hotplug_lock){++++}-{0:0}:
        cpus_read_lock+0x2a/0xd0
        ring_buffer_resize+0x610/0x14e0
        __tracing_resize_ring_buffer.part.0+0x42/0x120
        tracing_set_tracer+0x7bd/0xa80
        tracing_set_trace_write+0x132/0x1e0
        vfs_write+0x21c/0xe80
        ksys_write+0xf9/0x1c0
        do_syscall_64+0x79/0x1c0
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 -> #0 (&buffer->mutex){+.+.}-{4:4}:
        __lock_acquire+0x1405/0x2210
        lock_acquire+0x174/0x310
        __mutex_lock+0x192/0x18c0
        ring_buffer_map+0x11c/0xe70
        tracing_buffers_mmap+0x1c4/0x3b0
        __mmap_region+0xd8d/0x1f70
        do_mmap+0x9d7/0x1010
        vm_mmap_pgoff+0x20b/0x390
        ksys_mmap_pgoff+0x2e9/0x440
        do_syscall_64+0x79/0x1c0
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 other info that might help us debug this:

 Chain exists of:
   &buffer->mutex --> &mm->mmap_lock --> &cpu_buffer->mapping_lock

  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(&cpu_buffer->mapping_lock);
                                lock(&mm->mmap_lock);
                                lock(&cpu_buffer->mapping_lock);
   lock(&buffer->mutex);

  *** DEADLOCK ***

 2 locks held by trace-cmd/1113:
  #0: ffff888106b847e0 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x192/0x390
  #1: ffff888100a5f9f8 (&cpu_buffer->mapping_lock){+.+.}-{4:4}, at: ring_buffer_map+0xcf/0xe70

 stack backtrace:
 CPU: 5 UID: 0 PID: 1113 Comm: trace-cmd Not tainted 6.15.0-rc7-test-00002-gfb7d03d8a82f #551 PREEMPT
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
 Call Trace:
  <TASK>
  dump_stack_lvl+0x6e/0xa0
  print_circular_bug.cold+0x178/0x1be
  check_noncircular+0x146/0x160
  __lock_acquire+0x1405/0x2210
  lock_acquire+0x174/0x310
  ? ring_buffer_map+0x11c/0xe70
  ? ring_buffer_map+0x11c/0xe70
  ? __mutex_lock+0x169/0x18c0
  __mutex_lock+0x192/0x18c0
  ? ring_buffer_map+0x11c/0xe70
  ? ring_buffer_map+0x11c/0xe70
  ? function_trace_call+0x296/0x370
  ? __pfx___mutex_lock+0x10/0x10
  ? __pfx_function_trace_call+0x10/0x10
  ? __pfx___mutex_lock+0x10/0x10
  ? _raw_spin_unlock+0x2d/0x50
  ? ring_buffer_map+0x11c/0xe70
  ? ring_buffer_map+0x11c/0xe70
  ? __mutex_lock+0x5/0x18c0
  ring_buffer_map+0x11c/0xe70
  ? do_raw_spin_lock+0x12d/0x270
  ? find_held_lock+0x2b/0x80
  ? _raw_spin_unlock+0x2d/0x50
  ? rcu_is_watching+0x15/0xb0
  ? _raw_spin_unlock+0x2d/0x50
  ? trace_preempt_on+0xd0/0x110
  tracing_buffers_mmap+0x1c4/0x3b0
  __mmap_region+0xd8d/0x1f70
  ? ring_buffer_lock_reserve+0x99/0xff0
  ? __pfx___mmap_region+0x10/0x10
  ? ring_buffer_lock_reserve+0x99/0xff0
  ? __pfx_ring_buffer_lock_reserve+0x10/0x10
  ? __pfx_ring_buffer_lock_reserve+0x10/0x10
  ? bpf_lsm_mmap_addr+0x4/0x10
  ? security_mmap_addr+0x46/0xd0
  ? lock_is_held_type+0xd9/0x130
  do_mmap+0x9d7/0x1010
  ? 0xffffffffc0370095
  ? __pfx_do_mmap+0x10/0x10
  vm_mmap_pgoff+0x20b/0x390
  ? __pfx_vm_mmap_pgoff+0x10/0x10
  ? 0xffffffffc0370095
  ksys_mmap_pgoff+0x2e9/0x440
  do_syscall_64+0x79/0x1c0
  entry_SYSCALL_64_after_hwframe+0x76/0x7e
 RIP: 0033:0x7fb0963a7de2
 Code: 00 00 00 0f 1f 44 00 00 41 f7 c1 ff 0f 00 00 75 27 55 89 cd 53 48 89 fb 48 85 ff 74 3b 41 89 ea 48 89 df b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 76 5b 5d c3 0f 1f 00 48 8b 05 e1 9f 0d 00 64
 RSP: 002b:00007ffdcc8fb878 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb0963a7de2
 RDX: 0000000000000001 RSI: 0000000000001000 RDI: 0000000000000000
 RBP: 0000000000000001 R08: 0000000000000006 R09: 0000000000000000
 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
 R13: 00007ffdcc8fbe68 R14: 00007fb096628000 R15: 00005633e01a5c90
  </TASK>

The issue is that cpus_read_lock() is taken within buffer->mutex. The
memory mapped pages are taken with the mmap_lock held. The buffer->mutex
is taken within the cpu_buffer->mapping_lock. There's quite a chain with
all these locks, where the deadlock can be fixed by moving the
cpus_read_lock() outside the taking of the buffer->mutex.

Cc: [email protected]
Cc: Masami Hiramatsu <[email protected]>
Cc: Mathieu Desnoyers <[email protected]>
Cc: Vincent Donnefort <[email protected]>
Link: https://lore.kernel.org/[email protected]
Fixes: 117c392 ("ring-buffer: Introducing ring-buffer mapping functions")
Signed-off-by: Steven Rostedt (Google) <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Manuel Diewald <[email protected]>
Signed-off-by: Mehmet Basaran <[email protected]>
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