| commit | 45c26b0736efad011b829d587fadf7085f948294 | |
| author | Andrey Ryabinin <aryabinin@virtuozzo.com> | |
| Tue, 15 Mar 2016 21:55:27 +0000 (15 14:55 -0700) | ||
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | |
| Wed, 17 Jan 2018 08:35:27 +0000 (17 09:35 +0100) | ||
| tree | 96bd24c735c9b5fa9aa88bc62fec180b4398897a | treesnapshot (tar.gz zip) |
| parent | 9780795fc1e5e3d6a98374df01d1f10372203fdf | commitdiff |
mm/page-writeback: fix dirty_ratelimit calculation
commit d59b1087a98e402ed9a7cc577f4da435f9a555f5 upstream.
Calculation of dirty_ratelimit sometimes is not correct. E.g. initial
values of dirty_ratelimit == INIT_BW and step == 0, lead to the
following result:
UBSAN: Undefined behaviour in ../mm/page-writeback.c:1286:7
shift exponent 25600 is too large for 64-bit type 'long unsigned int'
The fix is straightforward - make step 0 if the shift exponent is too
big.
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d59b1087a98e402ed9a7cc577f4da435f9a555f5 upstream.
Calculation of dirty_ratelimit sometimes is not correct. E.g. initial
values of dirty_ratelimit == INIT_BW and step == 0, lead to the
following result:
UBSAN: Undefined behaviour in ../mm/page-writeback.c:1286:7
shift exponent 25600 is too large for 64-bit type 'long unsigned int'
The fix is straightforward - make step 0 if the shift exponent is too
big.
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| mm/page-writeback.c | diffblobblamehistory |