4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: "Darrick J. Wong" <darrick.wong@xxxxxxxxxx> [ Upstream commit 08b005f1333154ae5b404ca28766e0ffb9f1c150 ] The sole remaining caller of kmem_zalloc_greedy is bulkstat, which uses it to grab 1-4 pages for staging of inobt records. The infinite loop in the greedy allocation function is causing hangs[1] in generic/269, so just get rid of the greedy allocator in favor of kmem_zalloc_large. This makes bulkstat somewhat more likely to ENOMEM if there's really no pages to spare, but eliminates a source of hangs. [1] http://lkml.kernel.org/r/20170301044634.rgidgdqqiiwsmfpj%40XZHOUW.usersys.redhat.com Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- v2: remove single-page fallback Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/xfs/kmem.c | 18 ------------------ fs/xfs/kmem.h | 2 -- fs/xfs/xfs_itable.c | 6 ++---- 3 files changed, 2 insertions(+), 24 deletions(-) --- a/fs/xfs/kmem.c +++ b/fs/xfs/kmem.c @@ -24,24 +24,6 @@ #include "kmem.h" #include "xfs_message.h" -/* - * Greedy allocation. May fail and may return vmalloced memory. - */ -void * -kmem_zalloc_greedy(size_t *size, size_t minsize, size_t maxsize) -{ - void *ptr; - size_t kmsize = maxsize; - - while (!(ptr = vzalloc(kmsize))) { - if ((kmsize >>= 1) <= minsize) - kmsize = minsize; - } - if (ptr) - *size = kmsize; - return ptr; -} - void * kmem_alloc(size_t size, xfs_km_flags_t flags) { --- a/fs/xfs/kmem.h +++ b/fs/xfs/kmem.h @@ -69,8 +69,6 @@ static inline void kmem_free(const void } -extern void *kmem_zalloc_greedy(size_t *, size_t, size_t); - static inline void * kmem_zalloc(size_t size, xfs_km_flags_t flags) { --- a/fs/xfs/xfs_itable.c +++ b/fs/xfs/xfs_itable.c @@ -351,7 +351,6 @@ xfs_bulkstat( xfs_agino_t agino; /* inode # in allocation group */ xfs_agnumber_t agno; /* allocation group number */ xfs_btree_cur_t *cur; /* btree cursor for ialloc btree */ - size_t irbsize; /* size of irec buffer in bytes */ xfs_inobt_rec_incore_t *irbuf; /* start of irec buffer */ int nirbuf; /* size of irbuf */ int ubcount; /* size of user's buffer */ @@ -378,11 +377,10 @@ xfs_bulkstat( *ubcountp = 0; *done = 0; - irbuf = kmem_zalloc_greedy(&irbsize, PAGE_SIZE, PAGE_SIZE * 4); + irbuf = kmem_zalloc_large(PAGE_SIZE * 4, KM_SLEEP); if (!irbuf) return -ENOMEM; - - nirbuf = irbsize / sizeof(*irbuf); + nirbuf = (PAGE_SIZE * 4) / sizeof(*irbuf); /* * Loop over the allocation groups, starting from the last