ACK: [SRU T/X/A/B][PATCH 0/1] LP: #1777029 - fscache: Fix hanging wait

[Khaled Elmously]

On 2018-06-15 12:33:28 , Daniel Axtens wrote:
> == SRU Justification ==
> 
> [Impact]
> Under heavy NFS + FSCache load, a user sometimes observes a hang in
> __fscache_wait_on_page_write+0x5f/0xa0.
> 
> Example traces:
> [<ffffffffc009f1bf>] __fscache_wait_on_page_write+0x5f/0xa0 [fscache]
> [<ffffffffc009f6da>] __fscache_uncache_all_inode_pages+0xba/0x120 [fscache]
> [<ffffffffc0419ece>] nfs_fscache_open_file+0x4e/0xc0 [nfs]
> 
> [<ffffffffc034f1bf>] __fscache_wait_on_page_write+0x5f/0xa0 [fscache]
> [<ffffffffc04104dc>] __nfs_fscache_invalidate_page+0x2c/0x80 [nfs]
> [<ffffffffc03fb543>] nfs_invalidate_page+0x63/0x90 [nfs]
> [<ffffffff811925c0>] truncate_inode_page+0x80/0x90
> 
> [Fix]
> Cherry-pick 2c98425720233ae3e135add0c7e869b32913502f from upstream,
> which is a patch from the FSCache maintainer.
> 
> [Testcase]
> The user has run a NFS stress-test with a similar home-grown patch,
> and will run a stress test on the proposed kernel.
> 
> [Regression Potential]
> Patch is limited to FSCache, so regression potential is limited.
> 
> David Howells (1):
>   fscache: Fix hanging wait on page discarded by writeback
> 
>  fs/fscache/page.c | 13 +++++++++----
>  1 file changed, 9 insertions(+), 4 deletions(-)
> 
Acked-by: Khalid Elmously <khalid.elmously at canonical.com>