The patch titled Subject: mm: fix division by 0 in percpu_pagelist_fraction() has been added to the -mm tree. Its filename is mm-fix-division-by-0-in-percpu_pagelist_fraction.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Sasha Levin <levinsasha928@xxxxxxxxx> Subject: mm: fix division by 0 in percpu_pagelist_fraction() percpu_pagelist_fraction_sysctl_handler() has only considered -EINVAL as a possible error from proc_dointvec_minmax(). If any other error is returned, it would proceed to divide by zero since percpu_pagelist_fraction wasn't getting initialized at any point. For example, writing 0 bytes into the proc file would trigger the issue. Signed-off-by: Sasha Levin <levinsasha928@xxxxxxxxx> Reviewed-by: Minchan Kim <minchan@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/page_alloc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff -puN mm/page_alloc.c~mm-fix-division-by-0-in-percpu_pagelist_fraction mm/page_alloc.c --- a/mm/page_alloc.c~mm-fix-division-by-0-in-percpu_pagelist_fraction +++ a/mm/page_alloc.c @@ -106,7 +106,7 @@ unsigned long totalreserve_pages __read_ */ unsigned long dirty_balance_reserve __read_mostly; -int percpu_pagelist_fraction; +int percpu_pagelist_fraction = 8; gfp_t gfp_allowed_mask __read_mostly = GFP_BOOT_MASK; #ifdef CONFIG_PM_SLEEP @@ -5271,7 +5271,7 @@ int percpu_pagelist_fraction_sysctl_hand int ret; ret = proc_dointvec_minmax(table, write, buffer, length, ppos); - if (!write || (ret == -EINVAL)) + if (!write || (ret < 0)) return ret; for_each_populated_zone(zone) { for_each_possible_cpu(cpu) { _ Subject: Subject: mm: fix division by 0 in percpu_pagelist_fraction() Patches currently in -mm which might be from levinsasha928@xxxxxxxxx are linux-next.patch mm-fix-division-by-0-in-percpu_pagelist_fraction.patch brlocks-lglocks-cleanups.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html