From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-132.freemail.mail.aliyun.com (out30-132.freemail.mail.aliyun.com [115.124.30.132]) (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 7DFA11BC3F; Wed, 30 Oct 2024 01:54:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.132 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730253253; cv=none; b=DBSSay57YBuDIlsxiY7FJLhtJHgADksvbBjJ24NYgxqZjPWx17UPO0VlYYhwRy+MjBYtRbjAtSANn/JExcePVxAUUeAYTMizDvNvVnZMeWvxc+JcCuNGKhB4fAIkTfWfVVEefjhdwDXIpP1VYTlGN7YqqICJJ7lRcGpoLd5tsgE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730253253; c=relaxed/simple; bh=wn4kpuFmeCG27j7Q5f1Et34O77xDdiyk5WPJjNIG1Do=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=X5YHDHNRHSYyjd0PK/+m8pT4zc2RrdRH1BE7M4qbvCHyMBglIVLjH3eI+xwFf+EGpSCLrf64zPzNmkzASpNXO1ht8rqaZPwW9E7JsvuIh4JSfjCo5IVpugdrgnUXvsSUeXn7cGqJs3ehOUc/hard7bS8i+l5GCDwrmrZtKiBQNI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=ZOmQ4E0G; arc=none smtp.client-ip=115.124.30.132 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="ZOmQ4E0G" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1730253246; h=Message-ID:Date:MIME-Version:Subject:To:From:Content-Type; bh=QVuP8bL2UthKGyf2UbcF1p2yjun+l2O30gXmPUgnGX4=; b=ZOmQ4E0GuzjdBFAZMcM+7Cz7W8Gc7kGMh2td12w+LThHhidBblj+EVUe6ScSSmu1NA+GMBYl2vB643VTVq3j6g/orJOIssHrF4F51pMYDlqabkp7KyHVct/boDdvzS4+qG8ORU7nTEgr9fZCurY6oH5NsBupQQFwd1S0R0yd2Es= Received: from 30.246.162.170(mailfrom:xueshuai@linux.alibaba.com fp:SMTPD_---0WIC1TDj_1730253241 cluster:ay36) by smtp.aliyun-inc.com; Wed, 30 Oct 2024 09:54:04 +0800 Message-ID: Date: Wed, 30 Oct 2024 09:54:00 +0800 Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v15 1/3] ACPI: APEI: send SIGBUS to current task if synchronous memory error not recovered To: Yazen Ghannam Cc: mark.rutland@arm.com, catalin.marinas@arm.com, mingo@redhat.com, robin.murphy@arm.com, Jonathan.Cameron@huawei.com, bp@alien8.de, rafael@kernel.org, wangkefeng.wang@huawei.com, tanxiaofei@huawei.com, mawupeng1@huawei.com, tony.luck@intel.com, linmiaohe@huawei.com, naoya.horiguchi@nec.com, james.morse@arm.com, tongtiangen@huawei.com, gregkh@linuxfoundation.org, will@kernel.org, jarkko@kernel.org, linux-acpi@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, linux-edac@vger.kernel.org, x86@kernel.org, justin.he@arm.com, ardb@kernel.org, ying.huang@intel.com, ashish.kalra@amd.com, baolin.wang@linux.alibaba.com, tglx@linutronix.de, dave.hansen@linux.intel.com, lenb@kernel.org, hpa@zytor.com, robert.moore@intel.com, lvying6@huawei.com, xiexiuqi@huawei.com, zhuo.song@linux.alibaba.com References: <20221027042445.60108-1-xueshuai@linux.alibaba.com> <20241028081142.66028-2-xueshuai@linux.alibaba.com> <20241029204848.GA1229628@yaz-khff2.amd.com> From: Shuai Xue In-Reply-To: <20241029204848.GA1229628@yaz-khff2.amd.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit 在 2024/10/30 04:48, Yazen Ghannam 写道: > On Mon, Oct 28, 2024 at 04:11:40PM +0800, Shuai Xue wrote: >> Synchronous error was detected as a result of user-space process accessing >> a 2-bit uncorrected error. The CPU will take a synchronous error exception >> such as Synchronous External Abort (SEA) on Arm64. The kernel will queue a >> memory_failure() work which poisons the related page, unmaps the page, and >> then sends a SIGBUS to the process, so that a system wide panic can be >> avoided. >> >> However, no memory_failure() work will be queued when abnormal synchronous >> errors occur. These errors can include situations such as invalid PA, >> unexpected severity, no memory failure config support, invalid GUID >> section, etc. In such case, the user-space process will trigger SEA again. >> This loop can potentially exceed the platform firmware threshold or even >> trigger a kernel hard lockup, leading to a system reboot. >> >> Fix it by performing a force kill if no memory_failure() work is queued >> for synchronous errors. >> >> Signed-off-by: Shuai Xue >> Reviewed-by: Jarkko Sakkinen >> Reviewed-by: Jonathan Cameron >> --- >> drivers/acpi/apei/ghes.c | 10 ++++++++++ >> 1 file changed, 10 insertions(+) >> >> diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c >> index ada93cfde9ba..f2ee28c44d7a 100644 >> --- a/drivers/acpi/apei/ghes.c >> +++ b/drivers/acpi/apei/ghes.c >> @@ -801,6 +801,16 @@ static bool ghes_do_proc(struct ghes *ghes, >> } >> } >> >> + /* >> + * If no memory failure work is queued for abnormal synchronous >> + * errors, do a force kill. >> + */ >> + if (sync && !queued) { >> + pr_err("%s:%d: hardware memory corruption (SIGBUS)\n", >> + current->comm, task_pid_nr(current)); > > I think it would help to include the GHES_PFX to indicate where this > message is coming from. The pr_fmt() macro could also be introduced > instead. Yes, GHES_PFX is a effective prefix and will be consistent to other message in GHES driver. Will add it in next version. What do you mean about pr_fmt()? > > Also, you may want to include the HW_ERR prefix. Not all kernel messages > related to hardware errors have this prefix today. But maybe that should > be changed so there is more consistent messaging. > Do we really need a HW_ERR prefix? The other case which use HW_ERR prefix are for hardware registers. The messages which send SIGBUS does not include HW_ERR, e.g. in kill_proc(), kill_procs(). pr_err("%#lx: Sending SIGBUS to %s:%d due to hardware memory corruption\n",... pr_err("%#lx: forcibly killing %s:%d because of failure to unmap corrupted page\n",... > Thanks, > Yazen Thanks for valuable comments. Best Regards, Shuai