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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BC1BFC4332F for ; Fri, 7 Oct 2022 21:50:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229776AbiJGVuu (ORCPT ); Fri, 7 Oct 2022 17:50:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33382 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229736AbiJGVum (ORCPT ); Fri, 7 Oct 2022 17:50:42 -0400 Received: from mail-pg1-x54a.google.com (mail-pg1-x54a.google.com [IPv6:2607:f8b0:4864:20::54a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 64BF483F0E for ; Fri, 7 Oct 2022 14:50:40 -0700 (PDT) Received: by mail-pg1-x54a.google.com with SMTP id s68-20020a632c47000000b00434e0e75076so3467983pgs.7 for ; Fri, 07 Oct 2022 14:50:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=O8RGq8MFx6yg4rvWL2LsrEdijzeVAuwua99jyz3WuY0=; b=Jm4fGwHaDYx7k9kxYT6mKkXoumBg51rFPtFVs1GUI0RDAED/uoDgT2YNed/lVzfR63 h0TE9R+NpFZlX072/6JitNBwgwOCkwj7MWGEJ9gSHP7juK93M7454+wy1rhY7QCus+rq wETw9tMRCilnjfF4BoNjlvaT7PaGOETx1PmHdjQz/gZyRd/vatqaqevPArtVOBLVpt7D qtJj4KgMq7PvlziZGs6v15glFw3zQHU4ozOBFV0tWIsguGo/HUN1RbaBMF2gkCbsHk42 I5W0wotcQX/ykvIoxcCSVRcdg3YeZdE/rgpy8N/In3caWqbczTRDU6ug4vJspOvW+iWe kC6g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=O8RGq8MFx6yg4rvWL2LsrEdijzeVAuwua99jyz3WuY0=; b=IP3w8tQexhDSVjZYjSDiRUmNP+h1nf7c71ccox5FJwqNBuSEN2iUzD4ZYxfsrxjuac ZSmsBv7TmOHql5HqnWW5pTZyr8unlkS1PALhrm/Gg/pcABoP//P09SwaMJI7gxAmYJjW oUCttofTGULAu0ROkyKL4fovYZWQ1Xuo8N7DNiinBA5NZqkD2kjmOmyVxJ7EhaPMwEoz T2ezqumSFCOFiCD33M8zR7n9siBVAeiTMbL/qL+PEe6ttXWPPdyGPj3N6r9DN3XuCGiM Mo5PC1PqU+bizfqY5Jmsc3pJ6j5GBrJ+Of51Qjw2RH/qQaDyOgfmHYEiTr0XhjOsbz+u 7LQw== X-Gm-Message-State: ACrzQf0ILh6OWfHhwq0Eo7J2L8OyCPpVj34Qvj69dWr2VDyKxBkvIeI3 99znRxohm8yJ6il4zhJbFeDTbasOdiNl X-Google-Smtp-Source: AMsMyM6u9ghCGBUvbM5APJ6uXbUZZysoD0yKXdfPswKlv7hHAgLwY/TTgHaNURF+8tLhijVM7Y0cjxypeMEW X-Received: from sgzhang.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:3d89]) (user=sgzhang job=sendgmr) by 2002:a62:1a8d:0:b0:544:1309:19f3 with SMTP id a135-20020a621a8d000000b00544130919f3mr7193381pfa.37.1665179440177; Fri, 07 Oct 2022 14:50:40 -0700 (PDT) Date: Fri, 7 Oct 2022 21:50:27 +0000 In-Reply-To: <20221007215027.918507-1-sgzhang@google.com> Mime-Version: 1.0 References: <20221007215027.918507-1-sgzhang@google.com> X-Mailer: git-send-email 2.38.0.rc1.362.ged0d419d3c-goog Message-ID: <20221007215027.918507-4-sgzhang@google.com> Subject: [PATCH v3 3/3] mtd: mtdoops: panic caused mtdoops to call mtdoops_erase function immediately From: Ray Zhang To: Miquel Raynal , Richard Weinberger , Vignesh Raghavendra Cc: linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org, Ray Zhang Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The panic function disables the local interrupts, preemption, and all other processors. When the invoked mtdoops needs to erase a used page, calling schedule_work() to do it will not work. Instead, just call mtdoops_erase function immediately. Tested: ~# echo c > /proc/sysrq-trigger [ 171.654759] sysrq: Trigger a crash [ 171.658325] Kernel panic - not syncing: sysrq triggered crash ...... [ 172.406423] mtdoops: not ready 34, 35 (erase immediately) [ 172.432285] mtdoops: ready 34, 35 [ 172.435633] Rebooting in 10 seconds.. Signed-off-by: Ray Zhang --- drivers/mtd/mtdoops.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) diff --git a/drivers/mtd/mtdoops.c b/drivers/mtd/mtdoops.c index eca48dff9b53..eccb7dea892f 100644 --- a/drivers/mtd/mtdoops.c +++ b/drivers/mtd/mtdoops.c @@ -168,7 +168,7 @@ static void mtdoops_workfunc_erase(struct work_struct *work) mtdoops_erase(cxt); } -static void mtdoops_inc_counter(struct mtdoops_context *cxt) +static void mtdoops_inc_counter(struct mtdoops_context *cxt, int panic) { cxt->nextpage++; if (cxt->nextpage >= cxt->oops_pages) @@ -178,12 +178,20 @@ static void mtdoops_inc_counter(struct mtdoops_context *cxt) cxt->nextcount = 0; if (page_is_used(cxt, cxt->nextpage)) { - schedule_work(&cxt->work_erase); - return; + pr_debug("mtdoops: not ready %d, %d (erase %s)\n", + cxt->nextpage, cxt->nextcount, + panic ? "immediately" : "scheduled"); + if (panic) { + /* In case of panic, erase immediately */ + mtdoops_erase(cxt); + } else { + /* Otherwise, schedule work to erase it "nicely" */ + schedule_work(&cxt->work_erase); + } + } else { + pr_debug("mtdoops: ready %d, %d (no erase)\n", + cxt->nextpage, cxt->nextcount); } - - pr_debug("mtdoops: ready %d, %d (no erase)\n", - cxt->nextpage, cxt->nextcount); } static void mtdoops_write(struct mtdoops_context *cxt, int panic) @@ -219,7 +227,7 @@ static void mtdoops_write(struct mtdoops_context *cxt, int panic) mark_page_used(cxt, cxt->nextpage); memset(cxt->oops_buf, 0xff, record_size); - mtdoops_inc_counter(cxt); + mtdoops_inc_counter(cxt, panic); out: clear_bit(0, &cxt->oops_buf_busy); } @@ -284,7 +292,7 @@ static void find_next_position(struct mtdoops_context *cxt) cxt->nextcount = maxcount; } - mtdoops_inc_counter(cxt); + mtdoops_inc_counter(cxt, 0); } static void mtdoops_do_dump(struct kmsg_dumper *dumper, -- 2.38.0.rc1.362.ged0d419d3c-goog