From patchwork Tue Jun 25 12:39:29 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jocelyn Falempe X-Patchwork-Id: 13711068 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 51DE2C2BBCA for ; Tue, 25 Jun 2024 12:40:35 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 8BEF210E2EA; Tue, 25 Jun 2024 12:40:34 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.b="b3Wlainb"; dkim-atps=neutral Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by gabe.freedesktop.org (Postfix) with ESMTPS id 0614910E2EA for ; Tue, 25 Jun 2024 12:40:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1719319231; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=7EWz1vItROBUOYp6sdJspiDZ8uU1laai0jDHb5Vv+x0=; b=b3Wlainbp6+Kp6pWoUvF4NiZp4uP3bwxnGQpDl0sbo3cjQNfYKKV8ldsn9CAZdGbHcXCck BRIxo3uT4Zf2VtTyd80mFpAgoQ8p8aoJUG+3OReeKBJ9LvhloCHPzNstOXxQXwqaoi1kje +GQ8kE8gNlU2KS2kqVa7R8NvgIs0duo= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-460-RCkWgWX_Nm-SSEzUrXPwMA-1; Tue, 25 Jun 2024 08:40:23 -0400 X-MC-Unique: RCkWgWX_Nm-SSEzUrXPwMA-1 Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 9D4051956096; Tue, 25 Jun 2024 12:40:17 +0000 (UTC) Received: from hydra.redhat.com (unknown [10.39.192.194]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id DCA1319560B2; Tue, 25 Jun 2024 12:40:06 +0000 (UTC) From: Jocelyn Falempe To: Michael Ellerman , Nicholas Piggin , Christophe Leroy , "Naveen N. Rao" , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Daniel Vetter , "K. Y. Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui , Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Kees Cook , Tony Luck , "Guilherme G. Piccoli" , Petr Mladek , Steven Rostedt , John Ogness , Sergey Senozhatsky , Jocelyn Falempe , Andrew Morton , Jani Nikula , Greg Kroah-Hartman , Kefeng Wang , Thomas Gleixner , Uros Bizjak , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-hyperv@vger.kernel.org, linux-mtd@lists.infradead.org, linux-hardening@vger.kernel.org Subject: [PATCH] printk: Add a short description string to kmsg_dump() Date: Tue, 25 Jun 2024 14:39:29 +0200 Message-ID: <20240625123954.211184-1-jfalempe@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" kmsg_dump doesn't forward the panic reason string to the kmsg_dumper callback. This patch adds a new parameter "const char *desc" to the kmsg_dumper dump() callback, and update all drivers that are using it. To avoid updating all kmsg_dump() call, it adds a kmsg_dump_desc() function and a macro for backward compatibility. I've written this for drm_panic, but it can be useful for other kmsg_dumper. It allows to see the panic reason, like "sysrq triggered crash" or "VFS: Unable to mount root fs on xxxx" on the drm panic screen. Signed-off-by: Jocelyn Falempe --- arch/powerpc/kernel/nvram_64.c | 3 ++- arch/powerpc/platforms/powernv/opal-kmsg.c | 3 ++- drivers/gpu/drm/drm_panic.c | 3 ++- drivers/hv/hv_common.c | 3 ++- drivers/mtd/mtdoops.c | 3 ++- fs/pstore/platform.c | 3 ++- include/linux/kmsg_dump.h | 13 ++++++++++--- kernel/panic.c | 2 +- kernel/printk/printk.c | 8 +++++--- 9 files changed, 28 insertions(+), 13 deletions(-) base-commit: f76698bd9a8ca01d3581236082d786e9a6b72bb7 diff --git a/arch/powerpc/kernel/nvram_64.c b/arch/powerpc/kernel/nvram_64.c index e385d3164648c..6b3a80d8cfa64 100644 --- a/arch/powerpc/kernel/nvram_64.c +++ b/arch/powerpc/kernel/nvram_64.c @@ -643,7 +643,8 @@ void __init nvram_init_oops_partition(int rtas_partition_exists) * partition. If that's too much, go back and capture uncompressed text. */ static void oops_to_nvram(struct kmsg_dumper *dumper, - enum kmsg_dump_reason reason) + enum kmsg_dump_reason reason, + const char *desc) { struct oops_log_info *oops_hdr = (struct oops_log_info *)oops_buf; static unsigned int oops_count = 0; diff --git a/arch/powerpc/platforms/powernv/opal-kmsg.c b/arch/powerpc/platforms/powernv/opal-kmsg.c index 6c3bc4b4da983..49b60de6feb04 100644 --- a/arch/powerpc/platforms/powernv/opal-kmsg.c +++ b/arch/powerpc/platforms/powernv/opal-kmsg.c @@ -20,7 +20,8 @@ * message, it just ensures that OPAL completely flushes the console buffer. */ static void kmsg_dump_opal_console_flush(struct kmsg_dumper *dumper, - enum kmsg_dump_reason reason) + enum kmsg_dump_reason reason, + const char *desc) { /* * Outside of a panic context the pollers will continue to run, diff --git a/drivers/gpu/drm/drm_panic.c b/drivers/gpu/drm/drm_panic.c index 293d4dcbc80da..88e9359fe6d78 100644 --- a/drivers/gpu/drm/drm_panic.c +++ b/drivers/gpu/drm/drm_panic.c @@ -604,7 +604,8 @@ static struct drm_plane *to_drm_plane(struct kmsg_dumper *kd) return container_of(kd, struct drm_plane, kmsg_panic); } -static void drm_panic(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason) +static void drm_panic(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason, + const char *desc) { struct drm_plane *plane = to_drm_plane(dumper); diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c index 9c452bfbd5719..b0786ee9c94e3 100644 --- a/drivers/hv/hv_common.c +++ b/drivers/hv/hv_common.c @@ -207,7 +207,8 @@ static int hv_die_panic_notify_crash(struct notifier_block *self, * buffer and call into Hyper-V to transfer the data. */ static void hv_kmsg_dump(struct kmsg_dumper *dumper, - enum kmsg_dump_reason reason) + enum kmsg_dump_reason reason, + const char *desc) { struct kmsg_dump_iter iter; size_t bytes_written; diff --git a/drivers/mtd/mtdoops.c b/drivers/mtd/mtdoops.c index 2f11585b5613e..c618999a96832 100644 --- a/drivers/mtd/mtdoops.c +++ b/drivers/mtd/mtdoops.c @@ -298,7 +298,8 @@ static void find_next_position(struct mtdoops_context *cxt) } static void mtdoops_do_dump(struct kmsg_dumper *dumper, - enum kmsg_dump_reason reason) + enum kmsg_dump_reason reason, + const char *desc) { struct mtdoops_context *cxt = container_of(dumper, struct mtdoops_context, dump); diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index 3497ede88aa01..a6ed5d56021ef 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -275,7 +275,8 @@ void pstore_record_init(struct pstore_record *record, * end of the buffer. */ static void pstore_dump(struct kmsg_dumper *dumper, - enum kmsg_dump_reason reason) + enum kmsg_dump_reason reason, + const char *desc) { struct kmsg_dump_iter iter; unsigned long total = 0; diff --git a/include/linux/kmsg_dump.h b/include/linux/kmsg_dump.h index 906521c2329ca..a8f8a6204542d 100644 --- a/include/linux/kmsg_dump.h +++ b/include/linux/kmsg_dump.h @@ -49,13 +49,15 @@ struct kmsg_dump_iter { */ struct kmsg_dumper { struct list_head list; - void (*dump)(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason); + void (*dump)(struct kmsg_dumper *dumper, + enum kmsg_dump_reason reason, + const char *desc); enum kmsg_dump_reason max_reason; bool registered; }; #ifdef CONFIG_PRINTK -void kmsg_dump(enum kmsg_dump_reason reason); +void kmsg_dump_desc(enum kmsg_dump_reason reason, const char *desc); bool kmsg_dump_get_line(struct kmsg_dump_iter *iter, bool syslog, char *line, size_t size, size_t *len); @@ -71,7 +73,7 @@ int kmsg_dump_unregister(struct kmsg_dumper *dumper); const char *kmsg_dump_reason_str(enum kmsg_dump_reason reason); #else -static inline void kmsg_dump(enum kmsg_dump_reason reason) +static inline void kmsg_dump_desc(enum kmsg_dump_reason reason, const char *desc) { } @@ -107,4 +109,9 @@ static inline const char *kmsg_dump_reason_str(enum kmsg_dump_reason reason) } #endif +static inline void kmsg_dump(enum kmsg_dump_reason reason) +{ + kmsg_dump_desc(reason, NULL); +} + #endif /* _LINUX_KMSG_DUMP_H */ diff --git a/kernel/panic.c b/kernel/panic.c index 0843a275531a7..0a8b29c44f3c1 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -378,7 +378,7 @@ void panic(const char *fmt, ...) panic_print_sys_info(false); - kmsg_dump(KMSG_DUMP_PANIC); + kmsg_dump_desc(KMSG_DUMP_PANIC, buf); /* * If you doubt kdump always works fine in any situation, diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index d0bff0b0abfdb..2e7195894e41a 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -4287,14 +4287,16 @@ const char *kmsg_dump_reason_str(enum kmsg_dump_reason reason) EXPORT_SYMBOL_GPL(kmsg_dump_reason_str); /** - * kmsg_dump - dump kernel log to kernel message dumpers. + * kmsg_dump_desc - dump kernel log to kernel message dumpers. * @reason: the reason (oops, panic etc) for dumping + * @desc: a short string to describe what caused the panic or oops. Can be NULL + * if no additional description is available. * * Call each of the registered dumper's dump() callback, which can * retrieve the kmsg records with kmsg_dump_get_line() or * kmsg_dump_get_buffer(). */ -void kmsg_dump(enum kmsg_dump_reason reason) +void kmsg_dump_desc(enum kmsg_dump_reason reason, const char *desc) { struct kmsg_dumper *dumper; @@ -4314,7 +4316,7 @@ void kmsg_dump(enum kmsg_dump_reason reason) continue; /* invoke dumper which will iterate over records */ - dumper->dump(dumper, reason); + dumper->dump(dumper, reason, desc); } rcu_read_unlock(); }