From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6DBE3C43334 for ; Thu, 16 Jun 2022 04:01:25 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id D8EF76B0072; Thu, 16 Jun 2022 00:01:24 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D3EA76B0073; Thu, 16 Jun 2022 00:01:24 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C06F66B0074; Thu, 16 Jun 2022 00:01:24 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id B15AA6B0072 for ; Thu, 16 Jun 2022 00:01:24 -0400 (EDT) Received: from smtpin12.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay11.hostedemail.com (Postfix) with ESMTP id 7D469803F4 for ; Thu, 16 Jun 2022 04:01:24 +0000 (UTC) X-FDA: 79582749288.12.5FD7B53 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) by imf11.hostedemail.com (Postfix) with ESMTP id E8D9340083 for ; Thu, 16 Jun 2022 04:01:23 +0000 (UTC) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 8A25921B23; Thu, 16 Jun 2022 04:01:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1655352082; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=bgNLYGf1glZIdXZGlzmxA8IAuKh2wnK1OZci4ltwfyc=; b=JOrO0qUj1wPpkHHssqXsc1EPBIq4rmeKqaZF2HEk8Ta+pAaB8gmr6RwnpkZ7/aJQLY2vzr hJJqKf+v16i6RfDRpqeLerVieWWwXMpJAV0E3i78NSDqoUekP55eyFCb+LIgjlg5My7bVU W1JaUYrRikgyutHuPUdCbyBXK5AYhtU= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1655352082; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=bgNLYGf1glZIdXZGlzmxA8IAuKh2wnK1OZci4ltwfyc=; b=9tUF1fyuIB5clvr4NEqhevSkxVCAUsrhx3kauV3qIvFWMmQsAoull1LCnaisnGxZfjxLTq BO5BQlTHCIT1+rAg== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 0F6061344E; Thu, 16 Jun 2022 04:01:22 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id H7nsABKrqmKDLgAAMHmgww (envelope-from ); Thu, 16 Jun 2022 04:01:22 +0000 Date: Thu, 16 Jun 2022 06:01:20 +0200 From: Oscar Salvador To: zhenwei pi Cc: naoya.horiguchi@nec.com, akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, david@redhat.com, linmiaohe@huawei.com, gregkh@linuxfoundation.org Subject: Re: [PATCH v6 1/1] mm/memory-failure: disable unpoison once hw error happens Message-ID: References: <20220615093209.259374-1-pizhenwei@bytedance.com> <20220615093209.259374-2-pizhenwei@bytedance.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220615093209.259374-2-pizhenwei@bytedance.com> ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1655352084; a=rsa-sha256; cv=none; b=L7OGYCzU7/hENfCRDkNoqHEIx5cZ6WOu9Nb5UldnDod1qYJ56+mg6vR0noddyIysKY0rKX J8S/5CdM0XvVI7sqbec8iKZpR6KPrl7oZukuGN3kMk+PiJrwyVCNXbJopOILk0csuaF0xo 0edc4ybtjhqRiOJJEpUXUbfraDN2MwU= ARC-Authentication-Results: i=1; imf11.hostedemail.com; dkim=pass header.d=suse.de header.s=susede2_rsa header.b=JOrO0qUj; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=9tUF1fyu; spf=pass (imf11.hostedemail.com: domain of osalvador@suse.de designates 195.135.220.28 as permitted sender) smtp.mailfrom=osalvador@suse.de; dmarc=pass (policy=none) header.from=suse.de ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1655352084; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=bgNLYGf1glZIdXZGlzmxA8IAuKh2wnK1OZci4ltwfyc=; b=DO6MdMHuRn5R2knEea3TyFh7Nd7PpWRfBLA7YK8PJ3oTdQRVqp+axZUMjqTJO+Su+cGAR+ z6Pnr6J6Cddd2/Vl95CvHsTPClVB92rK5xNC4vPZ9I9qG3KHuUVFv09e+eYCUo0fZjLGC1 BCIkVuNZo2feSj+WKwugsuTdS0zPh/c= X-Stat-Signature: ksknff4nsiyw9iahsowy5ssa31nt3zne X-Rspamd-Queue-Id: E8D9340083 Authentication-Results: imf11.hostedemail.com; dkim=pass header.d=suse.de header.s=susede2_rsa header.b=JOrO0qUj; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=9tUF1fyu; spf=pass (imf11.hostedemail.com: domain of osalvador@suse.de designates 195.135.220.28 as permitted sender) smtp.mailfrom=osalvador@suse.de; dmarc=pass (policy=none) header.from=suse.de X-Rspam-User: X-Rspamd-Server: rspam02 X-HE-Tag: 1655352083-254094 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Jun 15, 2022 at 05:32:09PM +0800, zhenwei pi wrote: > Currently unpoison_memory(unsigned long pfn) is designed for soft > poison(hwpoison-inject) only. Since 17fae1294ad9d, the KPTE gets > cleared on a x86 platform once hardware memory corrupts. > > Unpoisoning a hardware corrupted page puts page back buddy only, > the kernel has a chance to access the page with *NOT PRESENT* KPTE. > This leads BUG during accessing on the corrupted KPTE. > > Suggested by David&Naoya, disable unpoison mechanism when a real HW error > happens to avoid BUG like this: > > Unpoison: Software-unpoisoned page 0x61234 > BUG: unable to handle page fault for address: ffff888061234000 > #PF: supervisor write access in kernel mode > #PF: error_code(0x0002) - not-present page > PGD 2c01067 P4D 2c01067 PUD 107267063 PMD 10382b063 PTE 800fffff9edcb062 > Oops: 0002 [#1] PREEMPT SMP NOPTI > CPU: 4 PID: 26551 Comm: stress Kdump: loaded Tainted: G M OE 5.18.0.bm.1-amd64 #7 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ... > RIP: 0010:clear_page_erms+0x7/0x10 > Code: ... > RSP: 0000:ffffc90001107bc8 EFLAGS: 00010246 > RAX: 0000000000000000 RBX: 0000000000000901 RCX: 0000000000001000 > RDX: ffffea0001848d00 RSI: ffffea0001848d40 RDI: ffff888061234000 > RBP: ffffea0001848d00 R08: 0000000000000901 R09: 0000000000001276 > R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000001 > R13: 0000000000000000 R14: 0000000000140dca R15: 0000000000000001 > FS: 00007fd8b2333740(0000) GS:ffff88813fd00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: ffff888061234000 CR3: 00000001023d2005 CR4: 0000000000770ee0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > PKRU: 55555554 > Call Trace: > > prep_new_page+0x151/0x170 > get_page_from_freelist+0xca0/0xe20 > ? sysvec_apic_timer_interrupt+0xab/0xc0 > ? asm_sysvec_apic_timer_interrupt+0x1b/0x20 > __alloc_pages+0x17e/0x340 > __folio_alloc+0x17/0x40 > vma_alloc_folio+0x84/0x280 > __handle_mm_fault+0x8d4/0xeb0 > handle_mm_fault+0xd5/0x2a0 > do_user_addr_fault+0x1d0/0x680 > ? kvm_read_and_reset_apf_flags+0x3b/0x50 > exc_page_fault+0x78/0x170 > asm_exc_page_fault+0x27/0x30 > > Fixes: 847ce401df392 ("HWPOISON: Add unpoisoning support") > Fixes: 17fae1294ad9d ("x86/{mce,mm}: Unmap the entire page if the whole page is affected and poisoned") > Cc: Naoya Horiguchi > Cc: David Hildenbrand > Cc: Oscar Salvador > Cc: Greg Kroah-Hartman > Acked-by: David Hildenbrand > Signed-off-by: zhenwei pi Reviewed-by: Oscar Salvador > --- > Documentation/vm/hwpoison.rst | 3 ++- > drivers/base/memory.c | 2 +- > include/linux/mm.h | 1 + > mm/hwpoison-inject.c | 2 +- > mm/madvise.c | 2 +- > mm/memory-failure.c | 12 ++++++++++++ > 6 files changed, 18 insertions(+), 4 deletions(-) > > diff --git a/Documentation/vm/hwpoison.rst b/Documentation/vm/hwpoison.rst > index c742de1769d1..b9d5253c1305 100644 > --- a/Documentation/vm/hwpoison.rst > +++ b/Documentation/vm/hwpoison.rst > @@ -120,7 +120,8 @@ Testing > unpoison-pfn > Software-unpoison page at PFN echoed into this file. This way > a page can be reused again. This only works for Linux > - injected failures, not for real memory failures. > + injected failures, not for real memory failures. Once any hardware > + memory failure happens, this feature is disabled. > > Note these injection interfaces are not stable and might change between > kernel versions > diff --git a/drivers/base/memory.c b/drivers/base/memory.c > index 084d67fd55cc..bc60c9cd3230 100644 > --- a/drivers/base/memory.c > +++ b/drivers/base/memory.c > @@ -558,7 +558,7 @@ static ssize_t hard_offline_page_store(struct device *dev, > if (kstrtoull(buf, 0, &pfn) < 0) > return -EINVAL; > pfn >>= PAGE_SHIFT; > - ret = memory_failure(pfn, 0); > + ret = memory_failure(pfn, MF_SW_SIMULATED); > if (ret == -EOPNOTSUPP) > ret = 0; > return ret ? ret : count; > diff --git a/include/linux/mm.h b/include/linux/mm.h > index bc8f326be0ce..4346e51484ba 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -3232,6 +3232,7 @@ enum mf_flags { > MF_MUST_KILL = 1 << 2, > MF_SOFT_OFFLINE = 1 << 3, > MF_UNPOISON = 1 << 4, > + MF_SW_SIMULATED = 1 << 5, > }; > extern int memory_failure(unsigned long pfn, int flags); > extern void memory_failure_queue(unsigned long pfn, int flags); > diff --git a/mm/hwpoison-inject.c b/mm/hwpoison-inject.c > index 5c0cddd81505..65e242b5a432 100644 > --- a/mm/hwpoison-inject.c > +++ b/mm/hwpoison-inject.c > @@ -48,7 +48,7 @@ static int hwpoison_inject(void *data, u64 val) > > inject: > pr_info("Injecting memory failure at pfn %#lx\n", pfn); > - err = memory_failure(pfn, 0); > + err = memory_failure(pfn, MF_SW_SIMULATED); > return (err == -EOPNOTSUPP) ? 0 : err; > } > > diff --git a/mm/madvise.c b/mm/madvise.c > index d7b4f2602949..0316bbc6441b 100644 > --- a/mm/madvise.c > +++ b/mm/madvise.c > @@ -1112,7 +1112,7 @@ static int madvise_inject_error(int behavior, > } else { > pr_info("Injecting memory failure for pfn %#lx at process virtual address %#lx\n", > pfn, start); > - ret = memory_failure(pfn, MF_COUNT_INCREASED); > + ret = memory_failure(pfn, MF_COUNT_INCREASED | MF_SW_SIMULATED); > if (ret == -EOPNOTSUPP) > ret = 0; > } > diff --git a/mm/memory-failure.c b/mm/memory-failure.c > index b85661cbdc4a..da39ec8afca8 100644 > --- a/mm/memory-failure.c > +++ b/mm/memory-failure.c > @@ -69,6 +69,8 @@ int sysctl_memory_failure_recovery __read_mostly = 1; > > atomic_long_t num_poisoned_pages __read_mostly = ATOMIC_LONG_INIT(0); > > +static bool hw_memory_failure __read_mostly = false; > + > static bool __page_handle_poison(struct page *page) > { > int ret; > @@ -1768,6 +1770,9 @@ int memory_failure(unsigned long pfn, int flags) > > mutex_lock(&mf_mutex); > > + if (!(flags & MF_SW_SIMULATED)) > + hw_memory_failure = true; > + > p = pfn_to_online_page(pfn); > if (!p) { > res = arch_memory_failure(pfn, flags); > @@ -2103,6 +2108,13 @@ int unpoison_memory(unsigned long pfn) > > mutex_lock(&mf_mutex); > > + if (hw_memory_failure) { > + unpoison_pr_info("Unpoison: Disabled after HW memory failure %#lx\n", > + pfn, &unpoison_rs); > + ret = -EOPNOTSUPP; > + goto unlock_mutex; > + } > + > if (!PageHWPoison(p)) { > unpoison_pr_info("Unpoison: Page was already unpoisoned %#lx\n", > pfn, &unpoison_rs); > -- > 2.20.1 > > -- Oscar Salvador SUSE Labs