From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Morse Subject: [PATCH v8 01/26] ACPI / APEI: Don't wait to serialise with oops messages when panic()ing Date: Tue, 29 Jan 2019 18:48:37 +0000 Message-ID: <20190129184902.102850-2-james.morse@arm.com> References: <20190129184902.102850-1-james.morse@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20190129184902.102850-1-james.morse@arm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu To: linux-acpi@vger.kernel.org Cc: Rafael Wysocki , Tony Luck , Marc Zyngier , Catalin Marinas , Will Deacon , Dongjiu Geng , linux-mm@kvack.org, Borislav Petkov , Naoya Horiguchi , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, Len Brown List-Id: linux-acpi@vger.kernel.org oops_begin() exists to group printk() messages with the oops message printed by die(). To reach this caller we know that platform firmware took this error first, then notified the OS via NMI with a 'panic' severity. Don't wait for another CPU to release the die-lock before panic()ing, our only goal is to print this fatal error and panic(). This code is always called in_nmi(), and since commit 42a0bb3f7138 ("printk/nmi: generic solution for safe printk in NMI"), it has been safe to call printk() from this context. Messages are batched in a per-cpu buffer and printed via irq-work, or a call back from panic(). Link: https://patchwork.kernel.org/patch/10313555/ Acked-by: Borislav Petkov Signed-off-by: James Morse --- Changes since v6: * Capitals in patch subject * Tinkered with the commit message. --- drivers/acpi/apei/ghes.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index f008ba7c9ced..0c46b79e31b1 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -33,7 +33,6 @@ #include #include #include -#include #include #include #include @@ -949,7 +948,6 @@ static int ghes_notify_nmi(unsigned int cmd, struct pt_regs *regs) sev = ghes_severity(ghes->estatus->error_severity); if (sev >= GHES_SEV_PANIC) { - oops_begin(); ghes_print_queued_estatus(); __ghes_panic(ghes); } -- 2.20.1