From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 751F828EE for ; Mon, 2 Jan 2023 11:28:42 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id F2094C433D2; Mon, 2 Jan 2023 11:28:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1672658922; bh=v0kGGHNNW8Opu5GPb0ENBLEfnSZTo+jwJLIuih8H7mk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MJJr4s4xbx3I5gfUzMxAAIdPKIsZvX+6dleNh3RKiemJOQfrQtRqtArrtLvgrFVdb 1G+4T6wgS9T1DxUvgKEp9WDOl3QjyzTiUS/qD7JUUfg4zw1i3P/h9vfBrVTqzyrrzX DuyDKu+wCzfvI0CkfU3V+RCN5GtRKBxa18DYo6vA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Qiujun Huang , WeiXiong Liao , Kees Cook Subject: [PATCH 6.0 51/74] pstore/zone: Use GFP_ATOMIC to allocate zone buffer Date: Mon, 2 Jan 2023 12:22:24 +0100 Message-Id: <20230102110554.271478079@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230102110552.061937047@linuxfoundation.org> References: <20230102110552.061937047@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Qiujun Huang commit 99b3b837855b987563bcfb397cf9ddd88262814b upstream. There is a case found when triggering a panic_on_oom, pstore fails to dump kmsg. Because psz_kmsg_write_record can't get the new buffer. Handle this by using GFP_ATOMIC to allocate a buffer at lower watermark. Signed-off-by: Qiujun Huang Fixes: 335426c6dcdd ("pstore/zone: Provide way to skip "broken" zone for MTD devices") Cc: WeiXiong Liao Cc: stable@vger.kernel.org Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/CAJRQjofRCF7wjrYmw3D7zd5QZnwHQq+F8U-mJDJ6NZ4bddYdLA@mail.gmail.com Signed-off-by: Greg Kroah-Hartman --- fs/pstore/zone.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/pstore/zone.c +++ b/fs/pstore/zone.c @@ -761,7 +761,7 @@ static inline int notrace psz_kmsg_write /* avoid destroying old data, allocate a new one */ len = zone->buffer_size + sizeof(*zone->buffer); zone->oldbuf = zone->buffer; - zone->buffer = kzalloc(len, GFP_KERNEL); + zone->buffer = kzalloc(len, GFP_ATOMIC); if (!zone->buffer) { zone->buffer = zone->oldbuf; return -ENOMEM;