From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-98.freemail.mail.aliyun.com (out30-98.freemail.mail.aliyun.com [115.124.30.98]) (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 B8030442C; Sat, 1 Mar 2025 05:54:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.98 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740808454; cv=none; b=X+lXouD/guoYJqt52DYicNeEZ3n/761U/uSx6XmOTJ63Xmg/0CriZPQcF43rOajcz5to2LOsVdI8vUP2IlASozGfzSmPmIksXAB9DApwylBO92OZXCf51re1sJimrnKJ+PnVr/SyQAeCc/tk3cC38eKLBEZXrkm57Wg2/kcWLls= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740808454; c=relaxed/simple; bh=n0KfLE0lUOtf7gNL1UolR8HQMLVPuZskvBP1OiG7xBc=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=foZBBzAD2nWt9QMh7GVyZDbLdr8fjeKpL2p49BFr82j34iAFHCu4pRBUhfbBOZlTjIDrMzj4mbxHWEsowTlOe5f1pQUM7GxnIMcrcTELVitiHeDhtm1HMroye83ZgMZ5YrqFEEg6dufFDDNKsQHrwbPTgsdHtDRelAkesd/N/Bg= 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=FkSNu3gG; arc=none smtp.client-ip=115.124.30.98 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="FkSNu3gG" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1740808447; h=Message-ID:Date:MIME-Version:Subject:To:From:Content-Type; bh=u2eBPXUoeE47ene7JxTrxiOlqV8Ez8vfqaaOsrJND8Q=; b=FkSNu3gGpjGVDtF8m0YtrfiXqTow0lnwduRq7u2M5VDp6QjU+4AuS6cu2Ujl5Xq3n64yj/sxtG/gWxlwH/s8F1joWWaJ1SS3+7ZdlcFVh7oqkHMyywUDRH64zbJpxs/s9f7yQ7U/9cWoX4Kn+BaJgyyeBjfaT2lbREaKdB/MCbw= Received: from 30.246.161.128(mailfrom:xueshuai@linux.alibaba.com fp:SMTPD_---0WQRfULE_1740808444 cluster:ay36) by smtp.aliyun-inc.com; Sat, 01 Mar 2025 13:54:05 +0800 Message-ID: Date: Sat, 1 Mar 2025 13:54:03 +0800 Precedence: bulk X-Mailing-List: linux-edac@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 0/5] mm/hwpoison: Fix regressions in memory failure handling To: Borislav Petkov Cc: "Luck, Tony" , "nao.horiguchi@gmail.com" , "tglx@linutronix.de" , "mingo@redhat.com" , "dave.hansen@linux.intel.com" , "x86@kernel.org" , "hpa@zytor.com" , "linmiaohe@huawei.com" , "akpm@linux-foundation.org" , "peterz@infradead.org" , "jpoimboe@kernel.org" , "linux-edac@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "baolin.wang@linux.alibaba.com" , "tianruidong@linux.alibaba.com" References: <7393bcfb-fe94-4967-b664-f32da19ae5f9@linux.alibaba.com> <20250218122417.GHZ7R78fPm32jKYUlx@fat_crate.local> <20250219081037.GAZ7WR_YmRtRvN_LKA@fat_crate.local> <20250220111903.GDZ7cPp1qVq3t9Jgs6@fat_crate.local> <4e13bef2-7402-4f75-8f0c-4a3cc210c5a6@linux.alibaba.com> <20250224220146.GBZ7zsSnXLftyqWzW_@fat_crate.local> <6f34c17c-4113-46d9-aa66-53ff5a1feed5@linux.alibaba.com> <20250228123553.GCZ8GtqbSq9kaYOaCi@fat_crate.local> From: Shuai Xue In-Reply-To: <20250228123553.GCZ8GtqbSq9kaYOaCi@fat_crate.local> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit 在 2025/2/28 20:35, Borislav Petkov 写道: > On Tue, Feb 25, 2025 at 09:51:25AM +0800, Shuai Xue wrote: >> It depends on the forked process which trying to read the poison. > > And? Can you try creating more processes and see what happens then? > Sure. The experimental model includes: 1. inject UE to a memory buffer 2. create 10 processes 3. all 10 process read the posioned buffer 4. 10 MCEs and 1 UCNA will be triggered 5. each process receives a SIGBUS Some details: #perf record -e probe:memory_failure -agR -- ./einj_mem_uc thread 0: thread vaddr = 0x7f65f08da400 paddr = 82702ec400 injecting ... >> trigger_thread >> trigger_thread >> trigger_thread >> trigger_thread >> trigger_thread >> trigger_thread >> trigger_thread >> trigger_thread >> trigger_thread >> trigger_thread signal 7 code 4 addr 0x7f65f08da000 page not present Unusual number of MCEs seen: 10 signal 7 code 4 addr 0x7f65f08da000 page not present Unusual number of MCEs seen: 10 signal 7 code 4 addr 0x7f65f08da000 page not present Unusual number of MCEs seen: 10 signal 7 code 4 addr 0x7f65f08da000 page not present Unusual number of MCEs seen: 10 signal 7 code 4 addr 0x7f65f08da000 page not present Unusual number of MCEs seen: 10 signal 7 code 4 addr 0x7f65f08da000 page not present Unusual number of MCEs seen: 10 signal 7 code 4 addr 0x7f65f08da000 page not present Unusual number of MCEs seen: 10 signal 7 code 4 addr 0x7f65f08da000 page not present Unusual number of MCEs seen: 10 signal 7 code 4 addr 0x7f65f08da000 page not present Unusual number of MCEs seen: 10 signal 7 code 4 addr 0x7f65f08da000 page not present Unusual number of MCEs seen: 10 Test passed [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.640 MB perf.data (11 samples) ] #perf script einj_mem_uc 1722254 [151] 695128.161644: probe:memory_failure: (ffffffffaa622db4) ffffffffaa622db5 memory_failure+0x5 ([kernel.kallsyms]) ffffffffaa2594fb kill_me_maybe+0x5b ([kernel.kallsyms]) ffffffffaa2fac29 task_work_run+0x59 ([kernel.kallsyms]) ffffffffaaf52347 irqentry_exit_to_user_mode+0x1c7 ([kernel.kallsyms]) ffffffffaaf50bce noist_exc_machine_check+0x3e ([kernel.kallsyms]) ffffffffaa001303 asm_exc_machine_check+0x33 ([kernel.kallsyms]) 405046 thread+0xe (/home/shawn.xs/ras-tools/einj_mem_uc) einj_mem_uc 1722255 [014] 695128.161712: probe:memory_failure: (ffffffffaa622db4) ffffffffaa622db5 memory_failure+0x5 ([kernel.kallsyms]) ffffffffaa2594fb kill_me_maybe+0x5b ([kernel.kallsyms]) ffffffffaa2fac29 task_work_run+0x59 ([kernel.kallsyms]) ffffffffaaf52347 irqentry_exit_to_user_mode+0x1c7 ([kernel.kallsyms]) ffffffffaaf50bce noist_exc_machine_check+0x3e ([kernel.kallsyms]) ffffffffaa001303 asm_exc_machine_check+0x33 ([kernel.kallsyms]) 405046 thread+0xe (/home/shawn.xs/ras-tools/einj_mem_uc) einj_mem_uc 1722256 [153] 695128.161716: probe:memory_failure: (ffffffffaa622db4) ffffffffaa622db5 memory_failure+0x5 ([kernel.kallsyms]) ffffffffaa2594fb kill_me_maybe+0x5b ([kernel.kallsyms]) ffffffffaa2fac29 task_work_run+0x59 ([kernel.kallsyms]) ffffffffaaf52347 irqentry_exit_to_user_mode+0x1c7 ([kernel.kallsyms]) ffffffffaaf50bce noist_exc_machine_check+0x3e ([kernel.kallsyms]) ffffffffaa001303 asm_exc_machine_check+0x33 ([kernel.kallsyms]) 405046 thread+0xe (/home/shawn.xs/ras-tools/einj_mem_uc) einj_mem_uc 1722257 [124] 695128.161759: probe:memory_failure: (ffffffffaa622db4) ffffffffaa622db5 memory_failure+0x5 ([kernel.kallsyms]) ffffffffaa2594fb kill_me_maybe+0x5b ([kernel.kallsyms]) ffffffffaa2fac29 task_work_run+0x59 ([kernel.kallsyms]) ffffffffaaf52347 irqentry_exit_to_user_mode+0x1c7 ([kernel.kallsyms]) ffffffffaaf50bce noist_exc_machine_check+0x3e ([kernel.kallsyms]) ffffffffaa001303 asm_exc_machine_check+0x33 ([kernel.kallsyms]) 405046 thread+0xe (/home/shawn.xs/ras-tools/einj_mem_uc) einj_mem_uc 1722258 [154] 695128.161782: probe:memory_failure: (ffffffffaa622db4) ffffffffaa622db5 memory_failure+0x5 ([kernel.kallsyms]) ffffffffaa2594fb kill_me_maybe+0x5b ([kernel.kallsyms]) ffffffffaa2fac29 task_work_run+0x59 ([kernel.kallsyms]) ffffffffaaf52347 irqentry_exit_to_user_mode+0x1c7 ([kernel.kallsyms]) ffffffffaaf50bce noist_exc_machine_check+0x3e ([kernel.kallsyms]) ffffffffaa001303 asm_exc_machine_check+0x33 ([kernel.kallsyms]) 405046 thread+0xe (/home/shawn.xs/ras-tools/einj_mem_uc) einj_mem_uc 1722259 [026] 695128.161819: probe:memory_failure: (ffffffffaa622db4) ffffffffaa622db5 memory_failure+0x5 ([kernel.kallsyms]) ffffffffaa2594fb kill_me_maybe+0x5b ([kernel.kallsyms]) ffffffffaa2fac29 task_work_run+0x59 ([kernel.kallsyms]) ffffffffaaf52347 irqentry_exit_to_user_mode+0x1c7 ([kernel.kallsyms]) ffffffffaaf50bce noist_exc_machine_check+0x3e ([kernel.kallsyms]) ffffffffaa001303 asm_exc_machine_check+0x33 ([kernel.kallsyms]) 405046 thread+0xe (/home/shawn.xs/ras-tools/einj_mem_uc) einj_mem_uc 1722260 [157] 695128.161852: probe:memory_failure: (ffffffffaa622db4) ffffffffaa622db5 memory_failure+0x5 ([kernel.kallsyms]) ffffffffaa2594fb kill_me_maybe+0x5b ([kernel.kallsyms]) ffffffffaa2fac29 task_work_run+0x59 ([kernel.kallsyms]) ffffffffaaf52347 irqentry_exit_to_user_mode+0x1c7 ([kernel.kallsyms]) ffffffffaaf50bce noist_exc_machine_check+0x3e ([kernel.kallsyms]) ffffffffaa001303 asm_exc_machine_check+0x33 ([kernel.kallsyms]) 405046 thread+0xe (/home/shawn.xs/ras-tools/einj_mem_uc) einj_mem_uc 1722261 [158] 695128.161895: probe:memory_failure: (ffffffffaa622db4) ffffffffaa622db5 memory_failure+0x5 ([kernel.kallsyms]) ffffffffaa2594fb kill_me_maybe+0x5b ([kernel.kallsyms]) ffffffffaa2fac29 task_work_run+0x59 ([kernel.kallsyms]) ffffffffaaf52347 irqentry_exit_to_user_mode+0x1c7 ([kernel.kallsyms]) ffffffffaaf50bce noist_exc_machine_check+0x3e ([kernel.kallsyms]) ffffffffaa001303 asm_exc_machine_check+0x33 ([kernel.kallsyms]) 405046 thread+0xe (/home/shawn.xs/ras-tools/einj_mem_uc) kworker/50:3-mm 1714430 [050] 695128.168736: probe:memory_failure: (ffffffffaa622db4) ffffffffaa622db5 memory_failure+0x5 ([kernel.kallsyms]) ffffffffaa25aa93 uc_decode_notifier+0x73 ([kernel.kallsyms]) ffffffffaa3068bb notifier_call_chain+0x5b ([kernel.kallsyms]) ffffffffaa306ae1 blocking_notifier_call_chain+0x41 ([kernel.kallsyms]) ffffffffaa25bbfe mce_gen_pool_process+0x3e ([kernel.kallsyms]) ffffffffaa2f455f process_one_work+0x19f ([kernel.kallsyms]) ffffffffaa2f509c worker_thread+0x20c ([kernel.kallsyms]) ffffffffaa2fec89 kthread+0xd9 ([kernel.kallsyms]) ffffffffaa245131 ret_from_fork+0x31 ([kernel.kallsyms]) ffffffffaa2076ca ret_from_fork_asm+0x1a ([kernel.kallsyms]) einj_mem_uc 1722252 [050] 695128.183025: probe:memory_failure: (ffffffffaa622db4) ffffffffaa622db5 memory_failure+0x5 ([kernel.kallsyms]) ffffffffaa2594fb kill_me_maybe+0x5b ([kernel.kallsyms]) ffffffffaa2fac29 task_work_run+0x59 ([kernel.kallsyms]) ffffffffaaf52347 irqentry_exit_to_user_mode+0x1c7 ([kernel.kallsyms]) ffffffffaaf50bce noist_exc_machine_check+0x3e ([kernel.kallsyms]) ffffffffaa001303 asm_exc_machine_check+0x33 ([kernel.kallsyms]) 405046 thread+0xe (/home/shawn.xs/ras-tools/einj_mem_uc) einj_mem_uc 1722253 [051] 695128.191348: probe:memory_failure: (ffffffffaa622db4) ffffffffaa622db5 memory_failure+0x5 ([kernel.kallsyms]) ffffffffaa2594fb kill_me_maybe+0x5b ([kernel.kallsyms]) ffffffffaa2fac29 task_work_run+0x59 ([kernel.kallsyms]) ffffffffaaf52347 irqentry_exit_to_user_mode+0x1c7 ([kernel.kallsyms]) ffffffffaaf50bce noist_exc_machine_check+0x3e ([kernel.kallsyms]) ffffffffaa001303 asm_exc_machine_check+0x33 ([kernel.kallsyms]) 405046 thread+0xe (/home/shawn.xs/ras-tools/einj_mem_uc) >> IMHO, we should send a SIGBUS signal to the processes running on the CPUs that >> detect a memory error for dirty page, which is the current behavior in the >> memory_failure. > > And for all those other processes which do get to see the already > poisoned/clean page, they should continue on their merry way instead of > getting killed by a SIGBUS? > Yes, memory_failure() only sends a SIGBUS signal to the process that is actively reading a poisoned page. Other processes that share the poisoned page will not receive a SIGBUS signal unless they have the PF_MCE_EARLY flag set.[1] [1]https://lkml.kernel.org/r/20220218090118.1105-4-linmiaohe@huawei.com Thanks. Shuai