From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-184.mta0.migadu.com (out-184.mta0.migadu.com [91.218.175.184]) (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 CDE4E320CCD for ; Thu, 13 Nov 2025 06:40:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.184 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763016047; cv=none; b=jszIcbhgP5MVMKajEyUCnxs7l/OQZ+wBOM8UlsFqYw0jArzMtuiB8/EyP/GwcMJM+sgvFFN17m6vNLUmnwGa4yvdyIWySlOU1XNQYxZgPpZ8Rk0zm+/Yaq+g3GLf3cMg9LlLPpr3KPmxXLBiObdgALs0PqPblq2f48IU8xVXkUQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763016047; c=relaxed/simple; bh=YV5TspKFRq+OhrJyi6EvPKd+wYWRrbdPUuz4/OpJ54I=; h=Message-ID:Date:MIME-Version:Subject:To:References:From: In-Reply-To:Content-Type; b=SpWUTqLaohA0/NkD4wUnfkU+J1TaYSGdu4hGUw3+CKOrP8geA6XoEy5h62e1RLJX+Stitdms5n3cFoD4dden7Pb+ZXWIXbhNELDndzGeS3HwenPc+HSQ+SuLDMLh7awmiAzft1XYrXmLx/XGwOkqUxjjR5Q5iUJPVVYI/ALnpZU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=Fq/cANEo; arc=none smtp.client-ip=91.218.175.184 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="Fq/cANEo" Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1763016043; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=fkCE1gInQuvvwwsk2xlmj60hAQZ+WgZJydh2PsbRcuA=; b=Fq/cANEoPniBM6TdaWoHRi5OatCcmxKo/i1m6O3mqKUMAr6dhgSx44agkRugeV6mxcoAhY QRMyRNDPxcsJmSmfJeWS6ganiQdEycMzn0+KuXhgekgCoBT6LGKmHcf3tDLTvYVwzL2kw2 vAlNp3upKThiymPc0nRsO7Y2EE1bMV8= Date: Thu, 13 Nov 2025 14:40:19 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH v2 3/3] dm-pcache: zero cache_info before default init To: Li Chen , dm-devel@lists.linux.dev, linux-kernel@vger.kernel.org, Zheng Gu References: <20251111121337.1063443-1-me@linux.beauty> <20251111121337.1063443-4-me@linux.beauty> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Dongsheng Yang In-Reply-To: <20251111121337.1063443-4-me@linux.beauty> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT 在 11/11/2025 8:13 PM, Li Chen 写道: > From: Li Chen > > pcache_meta_find_latest() leaves whatever it last copied into the > caller’s buffer even when it returns NULL. For cache_info_init(), > that meant cache->cache_info could still contain CRC-bad garbage when > no valid metadata exists, leading later initialization paths to read > bogus flags. > > Explicitly memset cache->cache_info in cache_info_init_default() > so new-cache paths start from a clean slate. The default sequence > number assignment becomes redundant with this reset, so it drops out. > > Signed-off-by: Li Chen Reviewed-by： Dongsheng Yang > --- > drivers/md/dm-pcache/cache.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/md/dm-pcache/cache.c b/drivers/md/dm-pcache/cache.c > index d516d4904227..698697a7a73c 100644 > --- a/drivers/md/dm-pcache/cache.c > +++ b/drivers/md/dm-pcache/cache.c > @@ -181,7 +181,7 @@ static void cache_info_init_default(struct pcache_cache *cache) > { > struct pcache_cache_info *cache_info = &cache->cache_info; > > - cache_info->header.seq = 0; > + memset(cache_info, 0, sizeof(*cache_info)); > cache_info->n_segs = cache->cache_dev->seg_num; > cache_info_set_gc_percent(cache_info, PCACHE_CACHE_GC_PERCENT_DEFAULT); > }