tree 82ec5ca5172fbedf49d918ce5e5c453ac4eaef0b
parent ee9fa8f302dc1df10583fc043a91003e0a332d1b
author James Morse <james.morse@arm.com> 1548787717 +0000
committer Rafael J. Wysocki <rafael.j.wysocki@intel.com> 1549577444 +0100

ACPI / APEI: Don't wait to serialise with oops messages when panic()ing

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 <bp@suse.de>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>