From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from m16.mail.163.com (m16.mail.163.com [220.197.31.3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5F4EC3370EC; Sat, 8 Aug 2026 09:40:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=220.197.31.3 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786182035; cv=none; b=j8AcGVDrjgNiOOYkFHA+W3t40dl9t6WAtrizvTJxLyA3HrtRUq7Q7rTpsfy1qWUZW8qg++nkfGfy47h4orW7VRRwq1JS2jUFAy1d6FcTs3L06NXaSlqAUV19He5fXPOqdvCoQN2/cnjZyP4UL7tEmJNYAU8uxHsouOaNTN7bpho= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786182035; c=relaxed/simple; bh=gRV1kwqU5RHQTHlQfpmYtdV6xt00OI6I+Dow0n6sLoo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=oezDV5E8iLzTBleSMhMTYWYB2/RAHGwnUlBe1ucgYhQPJT9XPMGBhrmXJnsxE2hasuBMegfw53YRzJDLPahOX3M4QlzT+QkJQeN325INNGL7McZj1Ptta6GmrSw2YcuDxYOXvlQRe8O4YxKWoVfRzjcgvCJFQrEMIQ8NYxzuVIA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com; spf=pass smtp.mailfrom=163.com; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b=Oo3tU8Ay; arc=none smtp.client-ip=220.197.31.3 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=163.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="Oo3tU8Ay" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:To:Subject:Date:Message-ID:MIME-Version; bh=VU MOOEBQX+6lir6ARl1Glb8AZ5ih0WCL/+4lwXJl+Vo=; b=Oo3tU8AyMnXEomyka8 r6FmDIHXVz0qz87Sd6P1Aqhe2Fc/zwaqmn2NjlKptlmUcOS59EblX23BOe0NHIfV SbdSEZdY7mPpNxnKRGoCfHHuIGFKg+TbmB5GNkSMiauqZsYm9jiqL+NlyHuZrGfT g7T/Bv1/wvXxjqtsOMJDDDCRQ= Received: from localhost (unknown []) by gzga-smtp-mtada-g1-3 (Coremail) with SMTP id _____wC3DONb+XZq2dtFMg--.6252S2; Sat, 08 Aug 2026 17:39:40 +0800 (CST) From: Hui Su To: akpm@linux-foundation.org Cc: andreyknvl@gmail.com, dvyukov@google.com, glider@google.com, kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, qiang1.zhang@intel.com, ryabinin.a.a@gmail.com, sh_def@163.com, stable@vger.kernel.org, vincenzo.frascino@arm.com Subject: Re: [PATCH v2] kasan: fix cache shrink race with CPU hotplug Date: Sat, 8 Aug 2026 17:38:05 +0800 Message-ID: <20260808093803.3138988-3-sh_def@163.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260808003921.fdb0df9ee4417b38f15e8c68@linux-foundation.org> References: <20260808003921.fdb0df9ee4417b38f15e8c68@linux-foundation.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID:_____wC3DONb+XZq2dtFMg--.6252S2 X-Coremail-Antispam: 1Uf129KBjvdXoWrtr1kJrWxXF4UKF4UKF45KFg_yoWfWrb_Z3 48CFZ3KrZxXF1Dta10yryUJFZ0gayFv342q34UJanrAryYqF95GF4kWrnIgFZxKrZ3JasY yr1YqrZ7G3sFgjkaLaAFLSUrUUUUjb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUvcSsGvfC2KfnxnUUI43ZEXa7VUj2Q6DUUUUU== X-CM-SenderInfo: xvkbvvri6rljoofrz/xtbCwh3NLWp2+V24IAAA3f Thanks Andrew, On Sat, Aug 08, 2026 at 12:39:21AM -0700, Andrew Morton wrote: > AI review suggests that there's a pre-existing quarantine_size > accounting flaw later in this function: > > https://sashiko.dev/#/patchset/20260808031459.3032812-1-sh_def@163.com > > If true, I'm surprised this hasn't yet been reported. I'll take a closer look at this. If it turns out to be a real issue, I'll send a separate patch since it's pre-existing and unrelated to the hotplug race fix. > Also, I'd like to see a need_resched() wrapping that expensive > > /* Scanning whole quarantine can take a while. */ > raw_spin_unlock_irqrestore(&quarantine_lock, flags); > cond_resched(); > raw_spin_lock_irqsave(&quarantine_lock, flags); Good point, that makes sense. Would you prefer that I fold this into a v3 of this patch, or send it as a separate follow-up patch? Thanks, Hui