diff options
authorMandeep Singh Baines <msb@chromium.org>2011-07-26 16:08:54 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-07-26 16:49:45 -0700
commitc958474b6d721ff09e4abf143efc07365d63aea5 (patch)
parent4302fbc8ec2ccae279c939f241bf8ce64e1a0bb7 (diff)
panic, vt: do not force oops output when panic_timeout < 0
Don't force output if you intend to reboot immediately. In this patch, I'm disabling the functionality enabled by vc->vc_panic_force_write if panic_timeout < 0 (i.e. no timeout). vc_panic_force_write is only enabled for fb video consoles if the FBINFO_CAN_FORCE_OUTPUT flag is set. For our application, we're using ram_oops to preserved the panic in memory. We want to reliably, and as fast as possible, machine_restart. The vc_panic_force_write flag results in a bunch of graphics driver code to be invoked which slows down restart and decreases reliability. Since we're already storing the panic in RAM and are going to reboot immediately, there is no benefit in mode switching back to the vc in order to display the panic output. The log buffer will get flushed by the console_unblank() call so remote management consoles should see all output. Signed-off-by: Mandeep Singh Baines <msb@chromium.org> Cc: Huang Ying <ying.huang@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Olaf Hering <olaf@aepfle.de> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Cc: Dave Airlie <airlied@gmail.com> Cc: Greg Kroah-Hartman <gregkh@suse.de> Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 files changed, 1 insertions, 1 deletions
diff --git a/include/linux/vt_kern.h b/include/linux/vt_kern.h
index 4d05e14ea60c..c2164fad0083 100644
--- a/include/linux/vt_kern.h
+++ b/include/linux/vt_kern.h
@@ -137,7 +137,7 @@ int vty_init(const struct file_operations *console_fops);
static inline bool vt_force_oops_output(struct vc_data *vc)
- if (oops_in_progress && vc->vc_panic_force_write)
+ if (oops_in_progress && vc->vc_panic_force_write && panic_timeout >= 0)
return true;
return false;

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