summaryrefslogtreecommitdiff
path: root/net/wireless/lib80211.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/wireless/lib80211.c')
0 files changed, 0 insertions, 0 deletions
generated by cgit v1.2.3-54-g00ecf (git 2.39.0) at 2024-10-27 01:43:10 +0000
the workqueue processor and made requeueable to the time the mask was cleared. (B) fscache_raise_event() will only queue the object if it manages to set the event bit and the corresponding event_mask bit was set. The enqueuement is then deferred slightly whilst we get a ref on the object and get the per-CPU variable for workqueue congestion. This slight deferral slightly increases the probability by allowing extra time for the workqueue to make the item requeueable. Handle this by giving the dead state a processor function and checking the for the dead state address rather than seeing if the processor function is address 0x2. The dead state processor function can then set a flag to indicate that it's occurred and give a warning if it occurs more than once per object. If this race occurs, an oops similar to the following is seen (note the RIP value): BUG: unable to handle kernel NULL pointer dereference at 0000000000000002 IP: [<0000000000000002>] 0x1 PGD 0 Oops: 0010 [#1] SMP Modules linked in: ... CPU: 17 PID: 16077 Comm: kworker/u48:9 Not tainted 3.10.0-327.18.2.el7.x86_64 #1 Hardware name: HP ProLiant DL380 Gen9/ProLiant DL380 Gen9, BIOS P89 12/27/2015 Workqueue: fscache_object fscache_object_work_func [fscache] task: ffff880302b63980 ti: ffff880717544000 task.ti: ffff880717544000 RIP: 0010:[<0000000000000002>] [<0000000000000002>] 0x1 RSP: 0018:ffff880717547df8 EFLAGS: 00010202 RAX: ffffffffa0368640 RBX: ffff880edf7a4480 RCX: dead000000200200 RDX: 0000000000000002 RSI: 00000000ffffffff RDI: ffff880edf7a4480 RBP: ffff880717547e18 R08: 0000000000000000 R09: dfc40a25cb3a4510 R10: dfc40a25cb3a4510 R11: 0000000000000400 R12: 0000000000000000 R13: ffff880edf7a4510 R14: ffff8817f6153400 R15: 0000000000000600 FS: 0000000000000000(0000) GS:ffff88181f420000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000002 CR3: 000000000194a000 CR4: 00000000001407e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Stack: ffffffffa0363695 ffff880edf7a4510 ffff88093f16f900 ffff8817faa4ec00 ffff880717547e60 ffffffff8109d5db 00000000faa4ec18 0000000000000000 ffff8817faa4ec18 ffff88093f16f930 ffff880302b63980 ffff88093f16f900 Call Trace: [<ffffffffa0363695>] ? fscache_object_work_func+0xa5/0x200 [fscache] [<ffffffff8109d5db>] process_one_work+0x17b/0x470 [<ffffffff8109e4ac>] worker_thread+0x21c/0x400 [<ffffffff8109e290>] ? rescuer_thread+0x400/0x400 [<ffffffff810a5acf>] kthread+0xcf/0xe0 [<ffffffff810a5a00>] ? kthread_create_on_node+0x140/0x140 [<ffffffff816460d8>] ret_from_fork+0x58/0x90 [<ffffffff810a5a00>] ? kthread_create_on_node+0x140/0x140 Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Jeremy McNicoll <jeremymc@redhat.com> Tested-by: Frank Sorenson <sorenson@redhat.com> Tested-by: Benjamin Coddington <bcodding@redhat.com> Reviewed-by: Benjamin Coddington <bcodding@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> 2017-01-31fscache: Clear outstanding writes when disabling a cookieDavid Howells2-0/+11 fscache_disable_cookie() needs to clear the outstanding writes on the cookie it's disabling because they cannot be completed after. Without this, fscache_nfs_open_file() gets stuck because it disables the cookie when the file is opened for writing but can't uncache the pages till afterwards - otherwise there's a race between the open routine and anyone who already has it open R/O and is still reading from it. Looking in /proc/pid/stack of the offending process shows: [<ffffffffa0142883>] __fscache_wait_on_page_write+0x82/0x9b [fscache] [<ffffffffa014336e>] __fscache_uncache_all_inode_pages+0x91/0xe1 [fscache] [<ffffffffa01740fa>] nfs_fscache_open_file+0x59/0x9e [nfs] [<ffffffffa01ccf41>] nfs4_file_open+0x17f/0x1b8 [nfsv4] [<ffffffff8117350e>] do_dentry_open+0x16d/0x2b7 [<ffffffff811743ac>] vfs_open+0x5c/0x65 [<ffffffff81184185>] path_openat+0x785/0x8fb [<ffffffff81184343>] do_filp_open+0x48/0x9e [<ffffffff81174710>] do_sys_open+0x13b/0x1cb [<ffffffff811747b9>] SyS_open+0x19/0x1b [<ffffffff81001c44>] do_syscall_64+0x80/0x17a [<ffffffff8165c2da>] return_from_SYSCALL_64+0x0/0x7a [<ffffffffffffffff>] 0xffffffffffffffff Reported-by: Jianhong Yin <jiyin@redhat.com> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Jeff Layton <jlayton@redhat.com> Acked-by: Steve Dickson <steved@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> 2017-01-31FS-Cache: Initialise stores_lock in netfs cookieDavid Howells1-0/+1 Initialise the stores_lock in fscache netfs cookies. Technically, it shouldn't be necessary, since the netfs cookie is an index and stores no data, but initialising it anyway adds insignificant overhead. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Acked-by: Steve Dickson <steved@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> 2017-01-29Linux 4.10-rc6Linus Torvalds1-2/+2 2017-01-29drm/i915: Check for NULL i915_vma in intel_unpin_fb_obj()Linus Torvalds