From: Ben Hutchings Date: Sun, 2 Jan 2011 23:02:42 +0000 (+0000) Subject: watchdog: Improve initialisation error message and documentation X-Git-Tag: v2.6.36.3~28 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=36bd931c61a97d5b8f9bc3ded62c4e43b22c34ff;p=karo-tx-linux.git watchdog: Improve initialisation error message and documentation commit 551423748a4eba55f2eb0fc250d757986471f187 upstream. The error message 'NMI watchdog failed to create perf event...' does not make it clear that this is a fatal error for the watchdog. It also currently prints the error value as a pointer, rather than extracting the error code with PTR_ERR(). Fix that. Add a note to the description of the 'nowatchdog' kernel parameter to associate it with this message. Reported-by: Cesare Leonardi Signed-off-by: Ben Hutchings Cc: 599368@bugs.debian.org Cc: 608138@bugs.debian.org Cc: Don Zickus Cc: Frederic Weisbecker LKML-Reference: <1294009362.3167.126.camel@localhost> Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 8dd7248508a9..20ed4ccc2a22 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1745,7 +1745,7 @@ and is between 256 and 4096 characters. It is defined in the file nousb [USB] Disable the USB subsystem - nowatchdog [KNL] Disable the lockup detector. + nowatchdog [KNL] Disable the lockup detector (NMI watchdog). nowb [ARM] diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 7f9c3c52ecc1..e7f81f8bc43e 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -377,7 +377,8 @@ static int watchdog_nmi_enable(int cpu) goto out_save; } - printk(KERN_ERR "NMI watchdog failed to create perf event on cpu%i: %p\n", cpu, event); + printk(KERN_ERR "NMI watchdog disabled for cpu%i: unable to create perf event: %ld\n", + cpu, PTR_ERR(event)); return -1; /* success path */