On Wed, Mar 22, 2017 at 5:54 PM, Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> wrote: > On 03/22/2017 07:34 PM, Andrey Konovalov wrote: >> On Wed, Mar 22, 2017 at 5:06 PM, Andrey Ryabinin >> <aryabinin@xxxxxxxxxxxxx> wrote: >>> Disable kasan after the first report. There are several reasons for this: >>> * Single bug quite often has multiple invalid memory accesses causing >>> storm in the dmesg. >>> * Write OOB access might corrupt metadata so the next report will print >>> bogus alloc/free stacktraces. >>> * Reports after the first easily could be not bugs by itself but just side >>> effects of the first one. >>> >>> Given that multiple reports only do harm, it makes sense to disable >>> kasan after the first one. Except for the tests in lib/test_kasan.c >>> as we obviously want to see all reports from test. >> >> Hi Andrey, >> >> Could you make it configurable via CONFIG_KASAN_SOMETHING (which can >> default to showing only the first report)? > > I'd rather make this boot time configurable, but wouldn't want to without > a good reason. That would work for me. > > >> I sometimes use KASAN to see what bad accesses a particular bug >> causes, and seeing all of them (even knowing that they may be >> corrupt/induced) helps a lot. > > I'm wondering why you need to see all reports? To get a better picture of what are the consequences of a bug. For example whether it leads to some bad or controllable memory corruption. Sometimes it's easier to let KASAN track the memory accesses then do that manually. > >> >> Thanks! >> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
