for-5.1-rc6-tag

-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAlzC5YIACgkQxWXV+ddt
 WDvYuxAAprsX3QjNDurMnm32TKTzY1a4yjYNQZXxNUKYvDAt4sglUMIfY3kP4uVy
 te9GtbHf0XDFNX58LBdBo8tnA8H/TbUr2qOlmh1hRqF89VVUCHpWBkhtOpWtYNVP
 jyL+tModOQjzhjV3RD2m4qHL0Q3oJpoiC7o+kuLGP46NIzfHt/tD1iDIW0j3QJRL
 f1rviXFiheNsXoeuDv/Shj6jMy6tGFa9Ys6tVmWcOxHBHVTBu+GsJaG86p4X39Sj
 ffOUPF3Btug8Q5ALppX+tbWocScITJs//mJJq4FjdAt8Qn5gnJM3h87GEPj+RZJf
 EwDMyd9uOwk7/HKMTtasJ6LDMsycriZ4r4cPOh/bqKz+dAsMA2V+FsV+MDSzhJlw
 w0MLZc5ELzKY1jV2jm4KR1PClj+tQ4n8Jl2P/b87TP1rsJcjpDpOgUwXDBgJCXQg
 LqZ/quQgfg3Zpcp+lPlsVN7dgwAwNYGlcKmMDXOnzZYRT2nNS6c4yx3EpSOXf6BI
 t557BdfP/Kz23hLNuawdO33XOTxhutVd4gyghmz2VOwz8XbYKw9MoJgmODWzenM7
 QqbmQvoKx82hHFLc1WQDyZxk9mhmTetQTdE4rFb291oxFBn6cGglx2omHylfJ8LU
 P27vH68QgihkWs/WXrkktPzhwZVlOTlf+cCZ+h5PEw0z8k9kqWY=
 =efvr
 -----END PGP SIGNATURE-----

Merge tag 'for-5.1-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fix from David Sterba:
 "One patch to fix a crash in io submission path, due to memory
  allocation errors.

  In short, the multipage bio work that landed in 5.1 caused larger bios
  that in turn require larger temporary memory for checksums. The patch
  is a workaround, we're going to rework the allocation so it does not
  require the vmalloc fallback.

  It took a while to identify that it's caused by patches in 5.1 and not
  a patchset that did some changes in error handling in the code. I've
  tested it on various memory/cpu combinations, it could hit OOM but
  does not crash.

  The timestamp of the patch is less than a day due to updates in the
  changelog, tests were running meanwhile"

* tag 'for-5.1-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: Switch memory allocations in async csum calculation path to kvmalloc
This commit is contained in:
Linus Torvalds 2019-04-26 09:46:46 -07:00
commit d0473f978e
2 changed files with 13 additions and 5 deletions

View File

@ -7,6 +7,7 @@
#include <linux/slab.h>
#include <linux/pagemap.h>
#include <linux/highmem.h>
#include <linux/sched/mm.h>
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
@ -427,9 +428,13 @@ blk_status_t btrfs_csum_one_bio(struct inode *inode, struct bio *bio,
unsigned long this_sum_bytes = 0;
int i;
u64 offset;
unsigned nofs_flag;
nofs_flag = memalloc_nofs_save();
sums = kvzalloc(btrfs_ordered_sum_size(fs_info, bio->bi_iter.bi_size),
GFP_KERNEL);
memalloc_nofs_restore(nofs_flag);
sums = kzalloc(btrfs_ordered_sum_size(fs_info, bio->bi_iter.bi_size),
GFP_NOFS);
if (!sums)
return BLK_STS_RESOURCE;
@ -472,8 +477,10 @@ blk_status_t btrfs_csum_one_bio(struct inode *inode, struct bio *bio,
bytes_left = bio->bi_iter.bi_size - total_bytes;
sums = kzalloc(btrfs_ordered_sum_size(fs_info, bytes_left),
GFP_NOFS);
nofs_flag = memalloc_nofs_save();
sums = kvzalloc(btrfs_ordered_sum_size(fs_info,
bytes_left), GFP_KERNEL);
memalloc_nofs_restore(nofs_flag);
BUG_ON(!sums); /* -ENOMEM */
sums->len = bytes_left;
ordered = btrfs_lookup_ordered_extent(inode,

View File

@ -6,6 +6,7 @@
#include <linux/slab.h>
#include <linux/blkdev.h>
#include <linux/writeback.h>
#include <linux/sched/mm.h>
#include "ctree.h"
#include "transaction.h"
#include "btrfs_inode.h"
@ -442,7 +443,7 @@ void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
cur = entry->list.next;
sum = list_entry(cur, struct btrfs_ordered_sum, list);
list_del(&sum->list);
kfree(sum);
kvfree(sum);
}
kmem_cache_free(btrfs_ordered_extent_cache, entry);
}