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Currently, cpu_online_cores_map returns a mask, which for every core with at least one online thread, has the bit for thread 0 of the core set to 1, and the bits for all other threads of the core set to 0. But thread 0 of the core itself may not be online always. In such cases, if the returned mask is used for IPI, then it'll cause IPIs to be skipped on cores where the first thread is offline, because the IPI code refuses to send IPIs to offline threads. Fix this by setting the bit of the first online thread in the core. This is done by fixing this in the underlying function cpu_thread_mask_to_cores. The result has the property that for all cores with online threads, there is one bit set in the returned map. And further, all bits that are set in the returned map correspond to online threads. Signed-off-by: Shreyas B. Prabhu <[email protected]> Reviewed-by: Preeti U Murthy <[email protected]> [ Changelog from Michael Ellerman <[email protected]> ] Reviewed-by: Gautham R. Shenoy <[email protected]> Signed-off-by: Michael Ellerman <[email protected]>
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Broke the SMP=n build: http://kisskb.ellerman.id.au/kisskb/buildresult/12427399/ |
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Buildbot: OK |
This is a cleanup patch; doesn't change any functionality. Moves all cpuidle related code from setup.c to a new file. Signed-off-by: Shreyas B. Prabhu <[email protected]> Reviewed-by: Preeti U Murthy <[email protected]> [mpe: Fix the SMP=n build by including asm/smp.h in idle.c] Signed-off-by: Michael Ellerman <[email protected]>
…avior Fastsleep is one of the idle state which cpuidle subsystem currently uses on power8 machines. In this state L2 cache is brought down to a threshold voltage. Therefore when the core is in fastsleep, the communication between L2 and L3 needs to be fenced. But there is a bug in the current power8 chips surrounding this fencing. OPAL provides a workaround which precludes the possibility of hitting this bug. But running with this workaround applied causes checkstop if any correctable error in L2 cache directory is detected. Hence OPAL also provides a way to undo the workaround. In the existing implementation, workaround is applied by the last thread of the core entering fastsleep and undone by the first thread waking up. But this has a performance cost. These OPAL calls account for roughly 4000 cycles everytime the core has to enter or wakeup from fastsleep. This patch introduces a sysfs attribute (fastsleep_workaround_applyonce) to choose the behavior of this workaround. By default, fastsleep_workaround_applyonce = 0. In this case, workaround is applied/undone everytime the core enters/exits fastsleep. fastsleep_workaround_applyonce = 1. In this case the workaround is applied once on all the cores and never undone. This can be triggered by echo 1 > /sys/devices/system/cpu/fastsleep_workaround_applyonce For simplicity this attribute can be modified only once. Implying, once fastsleep_workaround_applyonce is changed to 1, it cannot be reverted to the default state. Signed-off-by: Shreyas B. Prabhu <[email protected]> Reviewed-by: Preeti U Murthy <[email protected]> Signed-off-by: Michael Ellerman <[email protected]>
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Kisskb: OK (SMP fixed) |
mpe
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Sep 3, 2015
Nikolay has reported a hang when a memcg reclaim got stuck with the following backtrace: PID: 18308 TASK: ffff883d7c9b0a30 CPU: 1 COMMAND: "rsync" #0 __schedule at ffffffff815ab152 #1 schedule at ffffffff815ab76e #2 schedule_timeout at ffffffff815ae5e5 #3 io_schedule_timeout at ffffffff815aad6a #4 bit_wait_io at ffffffff815abfc6 #5 __wait_on_bit at ffffffff815abda5 #6 wait_on_page_bit at ffffffff8111fd4f #7 shrink_page_list at ffffffff81135445 #8 shrink_inactive_list at ffffffff81135845 #9 shrink_lruvec at ffffffff81135ead #10 shrink_zone at ffffffff811360c3 torvalds#11 shrink_zones at ffffffff81136eff torvalds#12 do_try_to_free_pages at ffffffff8113712f torvalds#13 try_to_free_mem_cgroup_pages at ffffffff811372be torvalds#14 try_charge at ffffffff81189423 torvalds#15 mem_cgroup_try_charge at ffffffff8118c6f5 torvalds#16 __add_to_page_cache_locked at ffffffff8112137d torvalds#17 add_to_page_cache_lru at ffffffff81121618 torvalds#18 pagecache_get_page at ffffffff8112170b torvalds#19 grow_dev_page at ffffffff811c8297 torvalds#20 __getblk_slow at ffffffff811c91d6 torvalds#21 __getblk_gfp at ffffffff811c92c1 torvalds#22 ext4_ext_grow_indepth at ffffffff8124565c torvalds#23 ext4_ext_create_new_leaf at ffffffff81246ca8 torvalds#24 ext4_ext_insert_extent at ffffffff81246f09 torvalds#25 ext4_ext_map_blocks at ffffffff8124a848 torvalds#26 ext4_map_blocks at ffffffff8121a5b7 torvalds#27 mpage_map_one_extent at ffffffff8121b1fa torvalds#28 mpage_map_and_submit_extent at ffffffff8121f07b torvalds#29 ext4_writepages at ffffffff8121f6d5 torvalds#30 do_writepages at ffffffff8112c490 torvalds#31 __filemap_fdatawrite_range at ffffffff81120199 torvalds#32 filemap_flush at ffffffff8112041c torvalds#33 ext4_alloc_da_blocks at ffffffff81219da1 torvalds#34 ext4_rename at ffffffff81229b91 torvalds#35 ext4_rename2 at ffffffff81229e32 torvalds#36 vfs_rename at ffffffff811a08a5 torvalds#37 SYSC_renameat2 at ffffffff811a3ffc torvalds#38 sys_renameat2 at ffffffff811a408e torvalds#39 sys_rename at ffffffff8119e51e torvalds#40 system_call_fastpath at ffffffff815afa89 Dave Chinner has properly pointed out that this is a deadlock in the reclaim code because ext4 doesn't submit pages which are marked by PG_writeback right away. The heuristic was introduced by commit e62e384 ("memcg: prevent OOM with too many dirty pages") and it was applied only when may_enter_fs was specified. The code has been changed by c3b94f4 ("memcg: further prevent OOM with too many dirty pages") which has removed the __GFP_FS restriction with a reasoning that we do not get into the fs code. But this is not sufficient apparently because the fs doesn't necessarily submit pages marked PG_writeback for IO right away. ext4_bio_write_page calls io_submit_add_bh but that doesn't necessarily submit the bio. Instead it tries to map more pages into the bio and mpage_map_one_extent might trigger memcg charge which might end up waiting on a page which is marked PG_writeback but hasn't been submitted yet so we would end up waiting for something that never finishes. Fix this issue by replacing __GFP_IO by may_enter_fs check (for case 2) before we go to wait on the writeback. The page fault path, which is the only path that triggers memcg oom killer since 3.12, shouldn't require GFP_NOFS and so we shouldn't reintroduce the premature OOM killer issue which was originally addressed by the heuristic. As per David Chinner the xfs is doing similar thing since 2.6.15 already so ext4 is not the only affected filesystem. Moreover he notes: : For example: IO completion might require unwritten extent conversion : which executes filesystem transactions and GFP_NOFS allocations. The : writeback flag on the pages can not be cleared until unwritten : extent conversion completes. Hence memory reclaim cannot wait on : page writeback to complete in GFP_NOFS context because it is not : safe to do so, memcg reclaim or otherwise. Cc: [email protected] # 3.9+ [[email protected]: corrected the control flow] Fixes: c3b94f4 ("memcg: further prevent OOM with too many dirty pages") Reported-by: Nikolay Borisov <[email protected]> Signed-off-by: Michal Hocko <[email protected]> Signed-off-by: Hugh Dickins <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
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It turns out that a PV domU also requires the "Xen PV" APIC driver. Otherwise, the flat driver is used and we get stuck in busy loops that never exit, such as in this stack trace: (gdb) target remote localhost:9999 Remote debugging using localhost:9999 __xapic_wait_icr_idle () at ./arch/x86/include/asm/ipi.h:56 56 while (native_apic_mem_read(APIC_ICR) & APIC_ICR_BUSY) (gdb) bt #0 __xapic_wait_icr_idle () at ./arch/x86/include/asm/ipi.h:56 #1 __default_send_IPI_shortcut (shortcut=<optimized out>, dest=<optimized out>, vector=<optimized out>) at ./arch/x86/include/asm/ipi.h:75 #2 apic_send_IPI_self (vector=246) at arch/x86/kernel/apic/probe_64.c:54 #3 0xffffffff81011336 in arch_irq_work_raise () at arch/x86/kernel/irq_work.c:47 #4 0xffffffff8114990c in irq_work_queue (work=0xffff88000fc0e400) at kernel/irq_work.c:100 #5 0xffffffff8110c29d in wake_up_klogd () at kernel/printk/printk.c:2633 #6 0xffffffff8110ca60 in vprintk_emit (facility=0, level=<optimized out>, dict=0x0 <irq_stack_union>, dictlen=<optimized out>, fmt=<optimized out>, args=<optimized out>) at kernel/printk/printk.c:1778 #7 0xffffffff816010c8 in printk (fmt=<optimized out>) at kernel/printk/printk.c:1868 #8 0xffffffffc00013ea in ?? () #9 0x0000000000000000 in ?? () Mailing-list-thread: https://lkml.org/lkml/2015/8/4/755 Signed-off-by: Jason A. Donenfeld <[email protected]> Cc: <[email protected]> Signed-off-by: David Vrabel <[email protected]>
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Sep 9, 2015
PID: 614 TASK: ffff882a739da580 CPU: 3 COMMAND: "ocfs2dc" #0 [ffff882ecc3759b0] machine_kexec at ffffffff8103b35d #1 [ffff882ecc375a20] crash_kexec at ffffffff810b95b5 #2 [ffff882ecc375af0] oops_end at ffffffff815091d8 #3 [ffff882ecc375b20] die at ffffffff8101868b #4 [ffff882ecc375b50] do_trap at ffffffff81508bb0 #5 [ffff882ecc375ba0] do_invalid_op at ffffffff810165e5 #6 [ffff882ecc375c40] invalid_op at ffffffff815116fb [exception RIP: ocfs2_ci_checkpointed+208] RIP: ffffffffa0a7e940 RSP: ffff882ecc375cf0 RFLAGS: 00010002 RAX: 0000000000000001 RBX: 000000000000654b RCX: ffff8812dc83f1f8 RDX: 00000000000017d9 RSI: ffff8812dc83f1f8 RDI: ffffffffa0b2c318 RBP: ffff882ecc375d20 R8: ffff882ef6ecfa60 R9: ffff88301f272200 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffffffffffff R13: ffff8812dc83f4f0 R14: 0000000000000000 R15: ffff8812dc83f1f8 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #7 [ffff882ecc375d28] ocfs2_check_meta_downconvert at ffffffffa0a7edbd [ocfs2] #8 [ffff882ecc375d38] ocfs2_unblock_lock at ffffffffa0a84af8 [ocfs2] #9 [ffff882ecc375dc8] ocfs2_process_blocked_lock at ffffffffa0a85285 [ocfs2] #10 [ffff882ecc375e18] ocfs2_downconvert_thread_do_work at ffffffffa0a85445 [ocfs2] torvalds#11 [ffff882ecc375e68] ocfs2_downconvert_thread at ffffffffa0a854de [ocfs2] torvalds#12 [ffff882ecc375ee8] kthread at ffffffff81090da7 torvalds#13 [ffff882ecc375f48] kernel_thread_helper at ffffffff81511884 assert is tripped because the tran is not checkpointed and the lock level is PR. Some time ago, chmod command had been executed. As result, the following call chain left the inode cluster lock in PR state, latter on causing the assert. system_call_fastpath -> my_chmod -> sys_chmod -> sys_fchmodat -> notify_change -> ocfs2_setattr -> posix_acl_chmod -> ocfs2_iop_set_acl -> ocfs2_set_acl -> ocfs2_acl_set_mode Here is how. 1119 int ocfs2_setattr(struct dentry *dentry, struct iattr *attr) 1120 { 1247 ocfs2_inode_unlock(inode, 1); <<< WRONG thing to do. .. 1258 if (!status && attr->ia_valid & ATTR_MODE) { 1259 status = posix_acl_chmod(inode, inode->i_mode); 519 posix_acl_chmod(struct inode *inode, umode_t mode) 520 { .. 539 ret = inode->i_op->set_acl(inode, acl, ACL_TYPE_ACCESS); 287 int ocfs2_iop_set_acl(struct inode *inode, struct posix_acl *acl, ... 288 { 289 return ocfs2_set_acl(NULL, inode, NULL, type, acl, NULL, NULL); 224 int ocfs2_set_acl(handle_t *handle, 225 struct inode *inode, ... 231 { .. 252 ret = ocfs2_acl_set_mode(inode, di_bh, 253 handle, mode); 168 static int ocfs2_acl_set_mode(struct inode *inode, struct buffer_head ... 170 { 183 if (handle == NULL) { >>> BUG: inode lock not held in ex at this point <<< 184 handle = ocfs2_start_trans(OCFS2_SB(inode->i_sb), 185 OCFS2_INODE_UPDATE_CREDITS); ocfs2_setattr.torvalds#1247 we unlock and at torvalds#1259 call posix_acl_chmod. When we reach ocfs2_acl_set_mode.torvalds#181 and do trans, the inode cluster lock is not held in EX mode (it should be). How this could have happended? We are the lock master, were holding lock EX and have released it in ocfs2_setattr.torvalds#1247. Note that there are no holders of this lock at this point. Another node needs the lock in PR, and we downconvert from EX to PR. So the inode lock is PR when do the trans in ocfs2_acl_set_mode.torvalds#184. The trans stays in core (not flushed to disc). Now another node want the lock in EX, downconvert thread gets kicked (the one that tripped assert abovt), finds an unflushed trans but the lock is not EX (it is PR). If the lock was at EX, it would have flushed the trans ocfs2_ci_checkpointed -> ocfs2_start_checkpoint before downconverting (to NULL) for the request. ocfs2_setattr must not drop inode lock ex in this code path. If it does, takes it again before the trans, say in ocfs2_set_acl, another cluster node can get in between, execute another setattr, overwriting the one in progress on this node, resulting in a mode acl size combo that is a mix of the two. Orabug: 20189959 Signed-off-by: Tariq Saeed <[email protected]> Reviewed-by: Mark Fasheh <[email protected]> Cc: Joel Becker <[email protected]> Cc: Joseph Qi <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
mpe
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Feb 7, 2019
Both gue_err() and gue6_err() incorrectly assume linear skbs. Fix them to use pskb_may_pull(). BUG: KMSAN: uninit-value in gue6_err+0x475/0xc40 net/ipv6/fou6.c:101 CPU: 0 PID: 18083 Comm: syz-executor1 Not tainted 5.0.0-rc1+ #7 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x173/0x1d0 lib/dump_stack.c:113 kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:600 __msan_warning+0x82/0xf0 mm/kmsan/kmsan_instr.c:313 gue6_err+0x475/0xc40 net/ipv6/fou6.c:101 __udp6_lib_err_encap_no_sk net/ipv6/udp.c:434 [inline] __udp6_lib_err_encap net/ipv6/udp.c:491 [inline] __udp6_lib_err+0x18d0/0x2590 net/ipv6/udp.c:522 udplitev6_err+0x118/0x130 net/ipv6/udplite.c:27 icmpv6_notify+0x462/0x9f0 net/ipv6/icmp.c:784 icmpv6_rcv+0x18ac/0x3fa0 net/ipv6/icmp.c:872 ip6_protocol_deliver_rcu+0xb5a/0x23a0 net/ipv6/ip6_input.c:394 ip6_input_finish net/ipv6/ip6_input.c:434 [inline] NF_HOOK include/linux/netfilter.h:289 [inline] ip6_input+0x2b6/0x350 net/ipv6/ip6_input.c:443 dst_input include/net/dst.h:450 [inline] ip6_rcv_finish+0x4e7/0x6d0 net/ipv6/ip6_input.c:76 NF_HOOK include/linux/netfilter.h:289 [inline] ipv6_rcv+0x34b/0x3f0 net/ipv6/ip6_input.c:272 __netif_receive_skb_one_core net/core/dev.c:4973 [inline] __netif_receive_skb net/core/dev.c:5083 [inline] process_backlog+0x756/0x10e0 net/core/dev.c:5923 napi_poll net/core/dev.c:6346 [inline] net_rx_action+0x78b/0x1a60 net/core/dev.c:6412 __do_softirq+0x53f/0x93a kernel/softirq.c:293 do_softirq_own_stack+0x49/0x80 arch/x86/entry/entry_64.S:1039 </IRQ> do_softirq kernel/softirq.c:338 [inline] __local_bh_enable_ip+0x16f/0x1a0 kernel/softirq.c:190 local_bh_enable+0x36/0x40 include/linux/bottom_half.h:32 rcu_read_unlock_bh include/linux/rcupdate.h:696 [inline] ip6_finish_output2+0x1d64/0x25f0 net/ipv6/ip6_output.c:121 ip6_finish_output+0xae4/0xbc0 net/ipv6/ip6_output.c:154 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip6_output+0x5ca/0x710 net/ipv6/ip6_output.c:171 dst_output include/net/dst.h:444 [inline] ip6_local_out+0x164/0x1d0 net/ipv6/output_core.c:176 ip6_send_skb+0xfa/0x390 net/ipv6/ip6_output.c:1727 udp_v6_send_skb+0x1733/0x1d20 net/ipv6/udp.c:1169 udpv6_sendmsg+0x424e/0x45d0 net/ipv6/udp.c:1466 inet_sendmsg+0x54a/0x720 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] ___sys_sendmsg+0xdb9/0x11b0 net/socket.c:2116 __sys_sendmmsg+0x580/0xad0 net/socket.c:2211 __do_sys_sendmmsg net/socket.c:2240 [inline] __se_sys_sendmmsg+0xbd/0xe0 net/socket.c:2237 __x64_sys_sendmmsg+0x56/0x70 net/socket.c:2237 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x457ec9 Code: 6d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f4a5204fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000457ec9 RDX: 00000000040001ab RSI: 0000000020000240 RDI: 0000000000000003 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4a520506d4 R13: 00000000004c4ce5 R14: 00000000004d85d8 R15: 00000000ffffffff Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:205 [inline] kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:159 kmsan_kmalloc+0xa6/0x130 mm/kmsan/kmsan_hooks.c:176 kmsan_slab_alloc+0xe/0x10 mm/kmsan/kmsan_hooks.c:185 slab_post_alloc_hook mm/slab.h:446 [inline] slab_alloc_node mm/slub.c:2754 [inline] __kmalloc_node_track_caller+0xe9e/0xff0 mm/slub.c:4377 __kmalloc_reserve net/core/skbuff.c:140 [inline] __alloc_skb+0x309/0xa20 net/core/skbuff.c:208 alloc_skb include/linux/skbuff.h:1012 [inline] alloc_skb_with_frags+0x1c7/0xac0 net/core/skbuff.c:5288 sock_alloc_send_pskb+0xafd/0x10a0 net/core/sock.c:2091 sock_alloc_send_skb+0xca/0xe0 net/core/sock.c:2108 __ip6_append_data+0x42ed/0x5dc0 net/ipv6/ip6_output.c:1443 ip6_append_data+0x3c2/0x650 net/ipv6/ip6_output.c:1619 icmp6_send+0x2f5c/0x3c40 net/ipv6/icmp.c:574 icmpv6_send+0xe5/0x110 net/ipv6/ip6_icmp.c:43 ip6_link_failure+0x5c/0x2c0 net/ipv6/route.c:2231 dst_link_failure include/net/dst.h:427 [inline] vti_xmit net/ipv4/ip_vti.c:229 [inline] vti_tunnel_xmit+0xf3b/0x1ea0 net/ipv4/ip_vti.c:265 __netdev_start_xmit include/linux/netdevice.h:4382 [inline] netdev_start_xmit include/linux/netdevice.h:4391 [inline] xmit_one net/core/dev.c:3278 [inline] dev_hard_start_xmit+0x604/0xc40 net/core/dev.c:3294 __dev_queue_xmit+0x2e48/0x3b80 net/core/dev.c:3864 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3897 neigh_direct_output+0x42/0x50 net/core/neighbour.c:1511 neigh_output include/net/neighbour.h:508 [inline] ip6_finish_output2+0x1d4e/0x25f0 net/ipv6/ip6_output.c:120 ip6_finish_output+0xae4/0xbc0 net/ipv6/ip6_output.c:154 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip6_output+0x5ca/0x710 net/ipv6/ip6_output.c:171 dst_output include/net/dst.h:444 [inline] ip6_local_out+0x164/0x1d0 net/ipv6/output_core.c:176 ip6_send_skb+0xfa/0x390 net/ipv6/ip6_output.c:1727 udp_v6_send_skb+0x1733/0x1d20 net/ipv6/udp.c:1169 udpv6_sendmsg+0x424e/0x45d0 net/ipv6/udp.c:1466 inet_sendmsg+0x54a/0x720 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] ___sys_sendmsg+0xdb9/0x11b0 net/socket.c:2116 __sys_sendmmsg+0x580/0xad0 net/socket.c:2211 __do_sys_sendmmsg net/socket.c:2240 [inline] __se_sys_sendmmsg+0xbd/0xe0 net/socket.c:2237 __x64_sys_sendmmsg+0x56/0x70 net/socket.c:2237 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 Fixes: b8a51b3 ("fou, fou6: ICMP error handlers for FoU and GUE") Signed-off-by: Eric Dumazet <[email protected]> Reported-by: syzbot <[email protected]> Cc: Stefano Brivio <[email protected]> Cc: Sabrina Dubroca <[email protected]> Signed-off-by: David S. Miller <[email protected]>
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Ido Schimmel says: ==================== mlxsw: Various fixes This patchset contains small fixes in mlxsw and one fix in the bridge driver. Patches #1-#4 perform small adjustments in PCI and FID code following recent tests that were performed on the Spectrum-2 ASIC. Patch #5 fixes the bridge driver to mark FDB entries that were added by user as such. Otherwise, these entries will be ignored by underlying switch drivers. Patch #6 fixes a long standing issue in mlxsw where the driver incorrectly programmed static FDB entries as both static and sticky. Patches #7-#8 add test cases for above mentioned bugs. Please consider patches #1, #2 and #4 for stable. ==================== Signed-off-by: David S. Miller <[email protected]>
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Feb 7, 2019
When option CONFIG_KASAN is enabled toghether with ftrace, function ftrace_graph_caller() gets in to a recursion, via functions kasan_check_read() and kasan_check_write(). Breakpoint 2, ftrace_graph_caller () at ../arch/arm64/kernel/entry-ftrace.S:179 179 mcount_get_pc x0 // function's pc (gdb) bt #0 ftrace_graph_caller () at ../arch/arm64/kernel/entry-ftrace.S:179 #1 0xffffff90101406c8 in ftrace_caller () at ../arch/arm64/kernel/entry-ftrace.S:151 #2 0xffffff90106fd084 in kasan_check_write (p=0xffffffc06c170878, size=4) at ../mm/kasan/common.c:105 #3 0xffffff90104a2464 in atomic_add_return (v=<optimized out>, i=<optimized out>) at ./include/generated/atomic-instrumented.h:71 #4 atomic_inc_return (v=<optimized out>) at ./include/generated/atomic-fallback.h:284 #5 trace_graph_entry (trace=0xffffffc03f5ff380) at ../kernel/trace/trace_functions_graph.c:441 #6 0xffffff9010481774 in trace_graph_entry_watchdog (trace=<optimized out>) at ../kernel/trace/trace_selftest.c:741 #7 0xffffff90104a185c in function_graph_enter (ret=<optimized out>, func=<optimized out>, frame_pointer=18446743799894897728, retp=<optimized out>) at ../kernel/trace/trace_functions_graph.c:196 #8 0xffffff9010140628 in prepare_ftrace_return (self_addr=18446743592948977792, parent=0xffffffc03f5ff418, frame_pointer=18446743799894897728) at ../arch/arm64/kernel/ftrace.c:231 #9 0xffffff90101406f4 in ftrace_graph_caller () at ../arch/arm64/kernel/entry-ftrace.S:182 Backtrace stopped: previous frame identical to this frame (corrupt stack?) (gdb) Rework so that the kasan implementation isn't traced. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Anders Roxell <[email protected]> Acked-by: Dmitry Vyukov <[email protected]> Tested-by: Dmitry Vyukov <[email protected]> Acked-by: Steven Rostedt (VMware) <[email protected]> Cc: Andrey Ryabinin <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
mpe
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Mar 4, 2020
journal_head::b_transaction and journal_head::b_next_transaction could
be accessed concurrently as noticed by KCSAN,
LTP: starting fsync04
/dev/zero: Can't open blockdev
EXT4-fs (loop0): mounting ext3 file system using the ext4 subsystem
EXT4-fs (loop0): mounted filesystem with ordered data mode. Opts: (null)
==================================================================
BUG: KCSAN: data-race in __jbd2_journal_refile_buffer [jbd2] / jbd2_write_access_granted [jbd2]
write to 0xffff99f9b1bd0e30 of 8 bytes by task 25721 on cpu 70:
__jbd2_journal_refile_buffer+0xdd/0x210 [jbd2]
__jbd2_journal_refile_buffer at fs/jbd2/transaction.c:2569
jbd2_journal_commit_transaction+0x2d15/0x3f20 [jbd2]
(inlined by) jbd2_journal_commit_transaction at fs/jbd2/commit.c:1034
kjournald2+0x13b/0x450 [jbd2]
kthread+0x1cd/0x1f0
ret_from_fork+0x27/0x50
read to 0xffff99f9b1bd0e30 of 8 bytes by task 25724 on cpu 68:
jbd2_write_access_granted+0x1b2/0x250 [jbd2]
jbd2_write_access_granted at fs/jbd2/transaction.c:1155
jbd2_journal_get_write_access+0x2c/0x60 [jbd2]
__ext4_journal_get_write_access+0x50/0x90 [ext4]
ext4_mb_mark_diskspace_used+0x158/0x620 [ext4]
ext4_mb_new_blocks+0x54f/0xca0 [ext4]
ext4_ind_map_blocks+0xc79/0x1b40 [ext4]
ext4_map_blocks+0x3b4/0x950 [ext4]
_ext4_get_block+0xfc/0x270 [ext4]
ext4_get_block+0x3b/0x50 [ext4]
__block_write_begin_int+0x22e/0xae0
__block_write_begin+0x39/0x50
ext4_write_begin+0x388/0xb50 [ext4]
generic_perform_write+0x15d/0x290
ext4_buffered_write_iter+0x11f/0x210 [ext4]
ext4_file_write_iter+0xce/0x9e0 [ext4]
new_sync_write+0x29c/0x3b0
__vfs_write+0x92/0xa0
vfs_write+0x103/0x260
ksys_write+0x9d/0x130
__x64_sys_write+0x4c/0x60
do_syscall_64+0x91/0xb05
entry_SYSCALL_64_after_hwframe+0x49/0xbe
5 locks held by fsync04/25724:
#0: ffff99f9911093f8 (sb_writers#13){.+.+}, at: vfs_write+0x21c/0x260
#1: ffff99f9db4c0348 (&sb->s_type->i_mutex_key#15){+.+.}, at: ext4_buffered_write_iter+0x65/0x210 [ext4]
#2: ffff99f5e7dfcf58 (jbd2_handle){++++}, at: start_this_handle+0x1c1/0x9d0 [jbd2]
#3: ffff99f9db4c0168 (&ei->i_data_sem){++++}, at: ext4_map_blocks+0x176/0x950 [ext4]
#4: ffffffff99086b40 (rcu_read_lock){....}, at: jbd2_write_access_granted+0x4e/0x250 [jbd2]
irq event stamp: 1407125
hardirqs last enabled at (1407125): [<ffffffff980da9b7>] __find_get_block+0x107/0x790
hardirqs last disabled at (1407124): [<ffffffff980da8f9>] __find_get_block+0x49/0x790
softirqs last enabled at (1405528): [<ffffffff98a0034c>] __do_softirq+0x34c/0x57c
softirqs last disabled at (1405521): [<ffffffff97cc67a2>] irq_exit+0xa2/0xc0
Reported by Kernel Concurrency Sanitizer on:
CPU: 68 PID: 25724 Comm: fsync04 Tainted: G L 5.6.0-rc2-next-20200221+ #7
Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 07/10/2019
The plain reads are outside of jh->b_state_lock critical section which result
in data races. Fix them by adding pairs of READ|WRITE_ONCE().
Reviewed-by: Jan Kara <[email protected]>
Signed-off-by: Qian Cai <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Theodore Ts'o <[email protected]>
mpe
pushed a commit
that referenced
this pull request
Jun 21, 2021
ASan reported a memory leak caused by info_linear not being deallocated.
The info_linear was allocated during in perf_event__synthesize_one_bpf_prog().
This patch adds the corresponding free() when bpf_prog_info_node
is freed in perf_env__purge_bpf().
$ sudo ./perf record -- sleep 5
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.025 MB perf.data (8 samples) ]
=================================================================
==297735==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 7688 byte(s) in 19 object(s) allocated from:
#0 0x4f420f in malloc (/home/user/linux/tools/perf/perf+0x4f420f)
#1 0xc06a74 in bpf_program__get_prog_info_linear /home/user/linux/tools/lib/bpf/libbpf.c:11113:16
#2 0xb426fe in perf_event__synthesize_one_bpf_prog /home/user/linux/tools/perf/util/bpf-event.c:191:16
#3 0xb42008 in perf_event__synthesize_bpf_events /home/user/linux/tools/perf/util/bpf-event.c:410:9
#4 0x594596 in record__synthesize /home/user/linux/tools/perf/builtin-record.c:1490:8
#5 0x58c9ac in __cmd_record /home/user/linux/tools/perf/builtin-record.c:1798:8
#6 0x58990b in cmd_record /home/user/linux/tools/perf/builtin-record.c:2901:8
#7 0x7b2a20 in run_builtin /home/user/linux/tools/perf/perf.c:313:11
#8 0x7b12ff in handle_internal_command /home/user/linux/tools/perf/perf.c:365:8
#9 0x7b2583 in run_argv /home/user/linux/tools/perf/perf.c:409:2
#10 0x7b0d79 in main /home/user/linux/tools/perf/perf.c:539:3
torvalds#11 0x7fa357ef6b74 in __libc_start_main /usr/src/debug/glibc-2.33-8.fc34.x86_64/csu/../csu/libc-start.c:332:16
Signed-off-by: Riccardo Mancini <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Andrii Nakryiko <[email protected]>
Cc: Daniel Borkmann <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: John Fastabend <[email protected]>
Cc: KP Singh <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Martin KaFai Lau <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Song Liu <[email protected]>
Cc: Yonghong Song <[email protected]>
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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