linux-kernel - Re: [PATCH v17 1/3] ACPI: APEI: send SIGBUS to current task if synchronous memory error not recovered

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <2fb8b1e5-d606-47be-a79e-a4e37a3b8f7f@oracle.com>
Date: Mon, 16 Dec 2024 15:37:24 -0800
From: jane.chu@...cle.com
To: Shuai Xue <xueshuai@...ux.alibaba.com>, yazen.ghannam@....com,
        mark.rutland@....com, catalin.marinas@....com, mingo@...hat.com,
        robin.murphy@....com, Jonathan.Cameron@...wei.com, bp@...en8.de,
        rafael@...nel.org, linux-arm-kernel@...ts.infradead.org,
        wangkefeng.wang@...wei.com, tanxiaofei@...wei.com,
        mawupeng1@...wei.com, tony.luck@...el.com, linmiaohe@...wei.com,
        naoya.horiguchi@....com, james.morse@....com, tongtiangen@...wei.com,
        gregkh@...uxfoundation.org, will@...nel.org, jarkko@...nel.org
Cc: linux-acpi@...r.kernel.org, linux-mm@...ck.org,
        linux-kernel@...r.kernel.org, akpm@...ux-foundation.org,
        linux-edac@...r.kernel.org, x86@...nel.org, justin.he@....com,
        ardb@...nel.org, ying.huang@...el.com, ashish.kalra@....com,
        baolin.wang@...ux.alibaba.com, tglx@...utronix.de,
        dave.hansen@...ux.intel.com, lenb@...nel.org, hpa@...or.com,
        robert.moore@...el.com, lvying6@...wei.com, xiexiuqi@...wei.com,
        zhuo.song@...ux.alibaba.com
Subject: Re: [PATCH v17 1/3] ACPI: APEI: send SIGBUS to current task if
 synchronous memory error not recovered


On 12/1/2024 7:05 PM, 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 <xueshuai@...ux.alibaba.com>
> Reviewed-by: Jarkko Sakkinen <jarkko@...nel.org>
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@...wei.com>
> Reviewed-by: Yazen Ghannam <yazen.ghannam@....com>
> ---
>   drivers/acpi/apei/ghes.c | 11 +++++++++++
>   1 file changed, 11 insertions(+)
>
> diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
> index a2491905f165..106486bdfefc 100644
> --- a/drivers/acpi/apei/ghes.c
> +++ b/drivers/acpi/apei/ghes.c
> @@ -801,6 +801,17 @@ 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) {
> +		dev_err(ghes->dev,
> +			HW_ERR GHES_PFX "%s:%d: synchronous unrecoverable error (SIGBUS)\n",
> +			current->comm, task_pid_nr(current));
> +		force_sig(SIGBUS);
> +	}
> +
>   	return queued;
>   }
>   

Looks good.

Reviewed-by: Jane Chu <jane.chu@...cle.com>

-jane