On 7/7/2017 4:06 PM, Horia Geantă wrote: > For more than 16 S/G entries, driver currently corrupts memory > on ARMv8, see below KASAN log. > Note: this does not reproduce on PowerPC due to different (smaller) > cache line size - 64 bytes on PPC vs. 128 bytes on ARMv8. > > One such use case is one of the cbc(aes) test vectors - with 8 S/G > entries and src != dst. Driver needs 1 (IV) + 2 x 8 = 17 entries, > which goes over the 16 S/G entries limit: > (CAAM_QI_MEMCACHE_SIZE - offsetof(struct ablkcipher_edesc, sgt)) / > sizeof(struct qm_sg_entry) = 256 / 16 = 16 S/Gs > > Fix this by: > -increasing object size in caamqicache pool from 512 to 768; this means > the maximum number of S/G entries grows from (at least) 16 to 32 > (again, for ARMv8 case of 128-byte cache line) > -add checks in the driver to fail gracefully (ENOMEM) in case the 32 S/G > entries limit is exceeded Looks like I forgot to add a check in one of the places - ablkcipher_giv_edesc_alloc(). Will fix this in v2. Horia
