On Tue, Oct 14, 2014 at 3:07 PM, Yury Gribov <y.gri...@samsung.com> wrote: > On 09/18/2014 01:57 PM, Jakub Jelinek wrote: >> On Thu, Sep 18, 2014 at 01:46:21PM +0400, Yury Gribov wrote: >>> Kernel Asan patches are currently being discussed in LKML. One of the >>> points>> raised during review was that KAsan requires GCC 5.0 which is >>> presumably >>> unstable (e.g. compilation of kernel modules has been broken for two >>> months >>> due to https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61848). >>> >>> Would it make sense to backport Kasan-related patches to 4.9 branch to >>> make >>> this feature more accessible to kernel developers? Quick analysis showed >>> that at the very least this would require >>> ... >>> Is it ok to backport these to 4.9? Note that I would discard patches for >>> other sanitizers (UBsan, Tsan). >> >> I'd say so, if it doesn't need any library changes >> (especially not any ABI >> visible ones, guess bugfixes could be acceptable). > > Finally got time to look into this. I've successfully backported 22 patches > to 4.9: > * bugfixes (12 patches) > * install Asan headers (1 patch) > * libsanitizer merge (1 patch) - this is questionable, see below for > discussion > * BUILT_IN_ASAN_REPORT_{LOAD,STORE}_N (2 patches) > * instrumentation with calls (1 patch) > * optimize strlen instrumentation (1 patch) > * move inlining to sanopt pass (2 patches) > * Kasan (2 patches) > > One problem is that for BUILT_IN_ASAN_REPORT_{LOAD,STORE}_N patch I need > libsanitizer APIs (__asan_loadN, __asan_storeN) which were introduced in a > giant libsanitizer merge in 5.0. In current patchset I backport the whole > merge patch (and a bunch of cherry-picks which followed it) but it changes > libsanitizer ABI (new version of __asan_init_vXXX, etc.) which is probably > undesirable. Another option would be to backport just the necessary minimum > (__asan_loadN, __asan_storeN). How should I proceed?
Backporting only __asan_loadN/__asan_storeN looks like the safest option to me. > Another question: Should I update patch CL dates for backported patches? If > not - should I insert them to CLs in chronological order or just stack on > top of previous contents? > > -Y
