From: Oleg Drokin <[email protected]>
New writeback changes in 4.2-RC1 have exposed that we incorrectly
set page_writeback on a page that is being written synchronously,
which aside from this new crash (dereference of NULL inode->i_wb
from set_page_writeback) likely threw off some related page
statistics in the past.
BUG: unable to handle kernel NULL pointer dereference at 0000000000000138
IP: [<ffffffff8140d90a>] __percpu_counter_add+0x1a/0x80
PGD 0
Oops: 0000 [#1] SMP DEBUG_PAGEALLOC
Modules linked in: osc(C) lmv(C) fld(C) mgc(C) lustre(C) mdc(C) fid(C) lov(C) ksocklnd(C) ptlrpc(C) obdclass(C) lnet(C) libcfs(C) loop sha512_generic crc32 rpcsec_gss_krb5 microcode joydev i2c_piix4 acpi_cpufreq pcspkr nfsd syscopyarea sysfillrect sysimgblt drm_kms_helper ttm drm serio_raw virtio_blk [last unloaded: libcfs]
CPU: 0 PID: 13328 Comm: cvs Tainted: G C 4.2.0-rc1-vm-nfs+ #30
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
task: ffff8800cc98a400 ti: ffff8801157e8000 task.ti: ffff8801157e8000
RIP: 0010:[<ffffffff8140d90a>] [<ffffffff8140d90a>] __percpu_counter_add+0x1a/0x80
RSP: 0018:ffff8801157eb698 EFLAGS: 00010086
RAX: 0000000000000003 RBX: ffffea0002b91cc0 RCX: 000000000000001a
RDX: 0000000000000020 RSI: 0000000000000001 RDI: 00000000000000e8
RBP: ffff8801157eb6b8 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 00000000000000e8
R13: 0000000000000001 R14: ffff8800673587a8 R15: ffff8800673589b0
FS: 00007f6718b89800(0000) GS:ffff88011f400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000138 CR3: 000000009d51c000 CR4: 00000000000007f0
Stack:
ffffffff811919e2 ffffea0002b91cc0 ffff880067358998 ffff880119419800
ffff8801157eb718 ffffffff81191a58 ffff8801157eb788 0000000000000282
ffff8800ce5ce920 0000000000000000 ffff8800a525af80 ffff880053f68f10
Call Trace:
[<ffffffff811919e2>] ? __test_set_page_writeback+0x72/0x240
[<ffffffff81191a58>] __test_set_page_writeback+0xe8/0x240
[<ffffffffa04e7a13>] vvp_page_prep_write+0x33/0xb0 [lustre]
[<ffffffffa028ad87>] cl_page_invoke+0x57/0x90 [obdclass]
[<ffffffffa028cc8d>] cl_page_prep+0x2d/0x180 [obdclass]
[<ffffffffa0545d84>] osc_io_submit+0x134/0x4a0 [osc]
[<ffffffffa02933a3>] cl_io_submit_rw+0x53/0xb0 [obdclass]
[<ffffffffa0483635>] lov_io_submit+0x3a5/0x570 [lov]
[<ffffffff810cb7bb>] ? lockdep_init_map+0x5b/0x6d0
[<ffffffffa02933a3>] cl_io_submit_rw+0x53/0xb0 [obdclass]
[<ffffffffa029428d>] cl_io_submit_sync+0xed/0x1c0 [obdclass]
[<ffffffffa04e881d>] vvp_page_sync_io.isra.15+0x4d/0x100 [lustre]
[<ffffffffa028dd2f>] ? cl_page_clip+0xff/0x130 [obdclass]
[<ffffffffa04e9f38>] vvp_io_commit_write+0x448/0x500 [lustre]
[<ffffffffa02939fa>] cl_io_commit_write+0x9a/0x130 [obdclass]
[<ffffffffa04cb222>] ll_commit_write+0xc2/0x230 [lustre]
[<ffffffffa04dbdaa>] ll_write_end+0x2a/0x50 [lustre]
[<ffffffff811851ba>] generic_perform_write+0xfa/0x1b0
[<ffffffff8121fd2e>] ? dentry_needs_remove_privs.part.16+0x1e/0x30
[<ffffffff811877d0>] __generic_file_write_iter+0x190/0x1f0
[<ffffffff8118791a>] generic_file_write_iter+0xea/0x1e0
[<ffffffffa04e8dd0>] vvp_io_write_start+0xa0/0x1e0 [lustre]
[<ffffffffa0292469>] cl_io_start+0x49/0x80 [obdclass]
[<ffffffffa0294803>] cl_io_loop+0x73/0xd0 [obdclass]
[<ffffffffa04b4ebf>] ll_file_io_generic+0x45f/0x4b0 [lustre]
[<ffffffffa04b504c>] ll_file_write_iter+0x6c/0xc0 [lustre]
[<ffffffff8120330a>] __vfs_write+0xaa/0xe0
[<ffffffff81203969>] vfs_write+0xa9/0x190
[<ffffffff812046c9>] SyS_write+0x49/0xa0
[<ffffffff81796572>] entry_SYSCALL_64_fastpath+0x16/0x7a
Code: 5b 41 5c 41 5d 41 5e 5d c3 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 55 41 54 53 49 89 fc 49 89 f5 48 83 ec 08 65 ff 05 8e d1 bf 7e <48> 8b 47 50 48 63 ca 65 8b 18 48 63 db 48 01 f3 48 39 cb 7d 0a
Signed-off-by: Jinshan Xiong <[email protected]>
Signed-off-by: Oleg Drokin <[email protected]>
Reviewed-on: http://review.whamcloud.com/15610
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-6854
---
drivers/staging/lustre/lustre/llite/vvp_page.c | 27 +++++++++++++++---------
drivers/staging/lustre/lustre/obdclass/cl_page.c | 3 ---
2 files changed, 17 insertions(+), 13 deletions(-)
diff --git a/drivers/staging/lustre/lustre/llite/vvp_page.c b/drivers/staging/lustre/lustre/llite/vvp_page.c
index 954ed08..a3cf5ad 100644
--- a/drivers/staging/lustre/lustre/llite/vvp_page.c
+++ b/drivers/staging/lustre/lustre/llite/vvp_page.c
@@ -227,11 +227,16 @@ static int vvp_page_prep_write(const struct lu_env *env,
struct cl_io *unused)
{
struct page *vmpage = cl2vm_page(slice);
+ struct cl_page *pg = slice->cpl_page;
LASSERT(PageLocked(vmpage));
LASSERT(!PageDirty(vmpage));
- set_page_writeback(vmpage);
+ /* ll_writepage path is not a sync write, so need to set page writeback
+ * flag */
+ if (!pg->cp_sync_io)
+ set_page_writeback(vmpage);
+
vvp_write_pending(cl2ccc(slice->cpl_obj), cl2ccc_page(slice));
return 0;
@@ -298,9 +303,6 @@ static void vvp_page_completion_write(const struct lu_env *env,
struct cl_page *pg = slice->cpl_page;
struct page *vmpage = cp->cpg_page;
- LASSERT(ergo(pg->cp_sync_io != NULL, PageLocked(vmpage)));
- LASSERT(PageWriteback(vmpage));
-
CL_PAGE_HEADER(D_PAGE, env, pg, "completing WRITE with %d\n", ioret);
/*
@@ -316,14 +318,19 @@ static void vvp_page_completion_write(const struct lu_env *env,
cp->cpg_write_queued = 0;
vvp_write_complete(cl2ccc(slice->cpl_obj), cp);
- /*
- * Only mark the page error only when it's an async write because
- * applications won't wait for IO to finish.
- */
- if (pg->cp_sync_io == NULL)
+ if (pg->cp_sync_io != NULL) {
+ LASSERT(PageLocked(vmpage));
+ LASSERT(!PageWriteback(vmpage));
+ } else {
+ LASSERT(PageWriteback(vmpage));
+ /*
+ * Only mark the page error only when it's an async write
+ * because applications won't wait for IO to finish.
+ */
vvp_vmpage_error(ccc_object_inode(pg->cp_obj), vmpage, ioret);
- end_page_writeback(vmpage);
+ end_page_writeback(vmpage);
+ }
}
/**
diff --git a/drivers/staging/lustre/lustre/obdclass/cl_page.c b/drivers/staging/lustre/lustre/obdclass/cl_page.c
index 282ae73..ca8b129 100644
--- a/drivers/staging/lustre/lustre/obdclass/cl_page.c
+++ b/drivers/staging/lustre/lustre/obdclass/cl_page.c
@@ -1189,9 +1189,6 @@ int cl_page_prep(const struct lu_env *env, struct cl_io *io,
if (result == 0)
cl_page_io_start(env, pg, crt);
- KLASSERT(ergo(crt == CRT_WRITE && pg->cp_type == CPT_CACHEABLE,
- equi(result == 0,
- PageWriteback(cl_page_vmpage(env, pg)))));
CL_PAGE_HEADER(D_TRACE, env, pg, "%d %d\n", crt, result);
return result;
}
--
2.1.0