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spf=pass (imf07.hostedemail.com: domain of andreyknvl@gmail.com designates 209.85.219.53 as permitted sender) smtp.mailfrom=andreyknvl@gmail.com Authentication-Results: imf07.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=V6UHbJdA; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (imf07.hostedemail.com: domain of andreyknvl@gmail.com designates 209.85.219.53 as permitted sender) smtp.mailfrom=andreyknvl@gmail.com X-Rspam-User: X-Rspamd-Queue-Id: 9083840067 X-Rspamd-Server: rspam06 X-Stat-Signature: 6xqiibixzn8nx6z4u7pscwjgynxbk6xg X-HE-Tag: 1658436108-757980 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Jul 19, 2022 at 1:41 PM Marco Elver wrote: > > > + for (u64 i = pos - 1; i != pos - 1 - KASAN_STACK_RING_SIZE; i--) { > > + if (alloc_found && free_found) > > + break; > > + > > + entry = &stack_ring.entries[i % KASAN_STACK_RING_SIZE]; > > + > > + /* Paired with smp_store_release() in save_stack_info(). */ > > + ptr = (void *)smp_load_acquire(&entry->ptr); > > + > > + if (kasan_reset_tag(ptr) != info->object || > > + get_tag(ptr) != get_tag(info->access_addr)) > > + continue; > > + > > + pid = READ_ONCE(entry->pid); > > + stack = READ_ONCE(entry->stack); > > + is_free = READ_ONCE(entry->is_free); > > + > > + /* Try detecting if the entry was changed while being read. */ > > + smp_mb(); > > + if (ptr != (void *)READ_ONCE(entry->ptr)) > > + continue; > > I thought the re-validation is no longer needed because of the rwlock > protection? Oh, yes, forgot to remove this. Will either do in v3 if there are more things to fix, or will just send a small fix-up patch if the rest of the series looks good. > The rest looks fine now. Thank you, Marco!