kernel/linux
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ synced 2026-10-16 22:39:48 +00:00
Code Issues Releases Packages Activity
linux/mm
History
Tejun Heo 20a63e5545 writeback: fix possible underflow in write bandwidth calculation 
commit c72efb658f upstream.

From 1ebf33901ecc75d9496862dceb1ef0377980587c Mon Sep 17 00:00:00 2001
From: Tejun Heo <tj@kernel.org>
Date: Mon, 23 Mar 2015 00:08:19 -0400

2f800fbd77 ("writeback: fix dirtied pages accounting on redirty")
introduced account_page_redirty() which reverts stat updates for a
redirtied page, making BDI_DIRTIED no longer monotonically increasing.

bdi_update_write_bandwidth() uses the delta in BDI_DIRTIED as the
basis for bandwidth calculation.  While unlikely, since the above
patch, the newer value may be lower than the recorded past value and
nunderflow the bandwidth calculation leading to a wild result.

Fix it by subtracing min of the old and new values when calculating
delta.  AFAIK, there hasn't been any report of it happening but the
resulting erratic behavior would be non-critical and temporary, so
it's possible that the issue is happening without being reported.  The
risk of the fix is very low, so tagged for -stable.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Greg Thelen <gthelen@google.com>
Fixes: 2f800fbd77 ("writeback: fix dirtied pages accounting on redirty")
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
History 2015-04-10 10:04:08 +01:00
..
backing-dev.c arch: Mass conversion of smp_mb__*() 2014-04-18 14:20:48 +02:00
balloon_compaction.c mm: print more details for bad_page() 2014-01-23 16:36:50 -08:00
bootmem.c mem-hotplug: reset node managed pages when hot-adding a new pgdat 2014-11-27 11:21:50 +00:00
cleancache.c mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE 2014-01-23 16:36:50 -08:00
compaction.c mm/compaction: fix wrong order check in compact_finished() 2015-03-02 15:04:20 +00:00
debug-pagealloc.c mm, x86: Remove debug_pagealloc_enabled 2011-12-06 09:24:07 +01:00
dmapool.c Fix unbalanced mutex in dma_pool_create(). 2014-10-05 13:41:09 -07:00
early_ioremap.c mm: create generic early_ioremap() support 2014-04-07 16:36:15 -07:00
fadvise.c teach SYSCALL_DEFINE<n> how to deal with long long/unsigned long long 2013-03-03 22:46:22 -05:00
failslab.c switch debugfs to umode_t 2012-01-03 22:54:56 -05:00
filemap.c mm: get rid of radix tree gfp mask for pagecache_get_page 2015-02-04 10:57:56 +00:00
filemap_xip.c seqcount: Add lockdep functionality to seqcount/seqlock structures 2013-11-06 12:40:26 +01:00
fremap.c mm: mark remap_file_pages() syscall as deprecated 2014-06-06 16:08:17 -07:00
frontswap.c mm: frontswap: invalidate expired data on a dup-store failure 2014-12-10 17:49:41 +00:00
gup.c mm/hugetlb: take page table lock in follow_huge_pmd() 2015-03-02 13:17:15 +00:00
highmem.c Some nice cleanups, and even a patch my wife did as a "live" demo for 2012-12-20 08:37:05 -08:00
huge_memory.c mm, thp: fix collapsing of hugepages on madvise 2014-11-13 11:48:56 +00:00
hugetlb.c mm/hugetlb: add migration entry check in __unmap_hugepage_range 2015-03-02 13:17:16 +00:00
hugetlb_cgroup.c cgroup: remove css_parent() 2014-05-16 13:22:48 -04:00
hwpoison-inject.c mm/hwpoison: add '#' to hwpoison_inject 2014-01-21 16:19:48 -08:00
init-mm.c atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
internal.h mm, compaction: properly signal and act upon lock and need_sched() contention 2014-06-04 16:54:11 -07:00
interval_tree.c mm: add CONFIG_DEBUG_VM_RB build option 2012-10-09 16:22:42 +09:00
iov_iter.c Fix thinko in iov_iter_single_seg_count 2014-11-27 11:21:48 +00:00
Kconfig mm/zsmalloc: make zsmalloc module-buildable 2014-06-04 16:54:14 -07:00
Kconfig.debug mm: more intensive memory corruption debugging 2012-01-10 16:30:42 -08:00
kmemcheck.c kmemcheck: Fix build errors due to missing slab.h 2010-03-30 22:02:32 +09:00
kmemleak-test.c mm/kmemleak-test.c: use pr_fmt for logging 2014-06-06 16:08:18 -07:00
kmemleak.c mm: introduce kmemleak_update_trace() 2014-06-06 16:08:17 -07:00
ksm.c vm: add VM_FAULT_SIGSEGV handling support 2015-02-04 10:58:27 +00:00
list_lru.c mm: keep page cache radix tree nodes in check 2014-04-03 16:21:01 -07:00
maccess.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
madvise.c mm: madvise: fix MADV_WILLNEED on shmem swapouts 2014-05-23 09:37:29 -07:00
Makefile mm: move get_user_pages()-related code to separate file 2014-06-04 16:54:04 -07:00
memblock.c memblock, memhotplug: fix wrong type in memblock_find_in_range_node(). 2014-10-05 13:41:03 -07:00
memcontrol.c memcg: remove extra newlines from memcg oom kill log 2015-02-04 10:58:34 +00:00
memory-failure.c mm: hwpoison: drop lru_add_drain_all() in __soft_offline_page() 2015-03-02 15:04:21 +00:00
memory.c mm/memory.c: actually remap enough memory 2015-03-02 15:04:20 +00:00
memory_hotplug.c mm/memory hotplug: postpone the reset of obsolete pgdat 2015-04-10 10:04:06 +01:00
mempolicy.c Merge branch 'for-3.16-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup 2014-07-10 11:38:23 -07:00
mempool.c mm/mempool.c: update the kmemleak stack trace for mempool allocations 2014-06-06 16:08:17 -07:00
migrate.c mm/hugetlb: take page table lock in follow_huge_pmd() 2015-03-02 13:17:15 +00:00
mincore.c mm + fs: prepare for non-page entries in page cache radix trees 2014-04-03 16:21:00 -07:00
mlock.c mm: try_to_unmap_cluster() should lock_page() before mlocking 2014-04-07 16:35:57 -07:00
mm_init.c mm: bring back /sys/kernel/mm 2014-01-27 21:02:39 -08:00
mmap.c mm: fix anon_vma->degree underflow in anon_vma endless growing prevention 2015-04-10 10:04:05 +01:00
mmu_context.c sched/mm: call finish_arch_post_lock_switch in idle_task_exit and use_mm 2014-02-21 08:50:17 +01:00
mmu_notifier.c mm: audit/fix non-modular users of module_init in core code 2014-01-23 16:36:52 -08:00
mmzone.c mm: numa: Change page last {nid,pid} into {cpu,pid} 2013-10-09 14:47:45 +02:00
mprotect.c mm: move mmu notifier call from change_protection to change_pmd_range 2014-04-07 16:35:50 -07:00
mremap.c mm, thp: close race between mremap() and split_huge_page() 2014-05-11 17:55:48 +09:00
msync.c msync: fix incorrect fstart calculation 2014-07-03 09:21:53 -07:00
nobootmem.c mem-hotplug: reset node managed pages when hot-adding a new pgdat 2014-11-27 11:21:50 +00:00
nommu.c mm/nommu.c: fix arithmetic overflow in __vm_enough_memory() 2015-03-02 13:17:17 +00:00
oom_kill.c OOM, PM: OOM killed task shouldn't escape PM suspend 2014-11-05 11:43:09 +00:00
page-writeback.c writeback: fix possible underflow in write bandwidth calculation 2015-04-10 10:04:08 +01:00
page_alloc.c mm: when stealing freepages, also take pages created by splitting buddy page 2015-03-02 13:17:16 +00:00
page_cgroup.c cgroup/kmemleak: add kmemleak_free() for cgroup deallocations. 2014-11-13 11:48:55 +00:00
page_io.c fix __swap_writepage() compile failure on old gcc versions 2014-06-14 19:30:48 -05:00
page_isolation.c mm: memory-hotplug: enable memory hotplug to handle hugepage 2013-09-11 15:57:48 -07:00
pagewalk.c mm: pagewalk: call pte_hole() for VM_PFNMAP during walk_page_range 2015-02-10 13:38:47 +00:00
percpu-km.c percpu: clear memory allocated with the km allocator 2010-10-02 10:28:42 +03:00
percpu-vm.c percpu: perform tlb flush after pcpu_map_pages() failure 2014-10-05 13:41:06 -07:00
percpu.c Revert "percpu: free percpu allocation info for uniprocessor system" 2014-11-14 15:20:06 +00:00
pgtable-generic.c mm: fix TLB flush race between migration, and change_protection_range 2013-12-18 19:04:51 -08:00
process_vm_access.c start adding the tag to iov_iter 2014-05-06 17:32:49 -04:00
quicklist.c mm: delete various needless include <linux/module.h> 2011-10-31 09:20:11 -04:00
readahead.c mm/readahead.c: inline ra_submit 2014-04-07 16:35:58 -07:00
rmap.c mm: fix anon_vma->degree underflow in anon_vma endless growing prevention 2015-04-10 10:04:05 +01:00
shmem.c shmem: fix nlink for rename overwrite directory 2014-10-05 13:41:03 -07:00
slab.c slab: fix nodeid bounds check for non-contiguous node IDs 2014-12-10 17:49:44 +00:00
slab.h memcg, slab: merge memcg_{bind,release}_pages to memcg_{un}charge_slab 2014-06-04 16:54:01 -07:00
slab_common.c Merge branch 'slab/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux into for-3.16-rcX 2014-07-22 18:38:27 -04:00
slob.c slab: get_online_mems for kmem_cache_{create,destroy,shrink} 2014-06-04 16:53:59 -07:00
slub.c slub: fix off by one in number of slab tests 2014-07-03 09:21:53 -07:00
sparse-vmemmap.c mm/sparse: use memblock apis for early memory allocations 2014-01-21 16:19:47 -08:00
sparse.c mm: use macros from compiler.h instead of __attribute__((...)) 2014-04-07 16:35:54 -07:00
swap.c mm: non-atomically mark page accessed during page cache allocation where possible 2014-06-04 16:54:10 -07:00
swap_state.c mm: page_alloc: convert hot/cold parameter and immediate callers to bool 2014-06-04 16:54:09 -07:00
swapfile.c mm/swapfile.c: delete the "last_in_cluster < scan_base" loop in the body of scan_swap_map() 2014-06-04 16:54:12 -07:00
truncate.c mm: Remove false WARN_ON from pagecache_isize_extended() 2014-11-13 11:49:03 +00:00
util.c vm_is_stack: use for_each_thread() rather then buggy while_each_thread() 2014-09-05 16:36:43 -07:00
vmacache.c mm,vmacache: optimize overflow system-wide flushing 2014-06-04 16:53:57 -07:00
vmalloc.c mm/vmalloc.c: export unmap_kernel_range() 2014-06-04 16:54:14 -07:00
vmpressure.c mm/vmpressure.c: fix race in vmpressure_work_fn() 2014-12-10 17:49:42 +00:00
vmscan.c mm, vmscan: prevent kswapd livelock due to pfmemalloc-throttled process being killed 2015-01-16 14:34:32 +00:00
vmstat.c mm: use the light version __mod_zone_page_state in mlocked_vma_newpage() 2014-06-04 16:54:07 -07:00
workingset.c mm: keep page cache radix tree nodes in check 2014-04-03 16:21:01 -07:00
zbud.c mm/zbud.c: make size unsigned like unique callsite 2014-06-04 16:54:13 -07:00
zsmalloc.c zsmalloc: fixup trivial zs size classes value in comments 2014-06-04 16:54:13 -07:00
zswap.c mm/zswap: NUMA aware allocation for zswap_dstmem 2014-06-04 16:54:14 -07:00