diff options
| author | Greg Kroah-Hartman <gregkh@suse.de> | 2010-10-21 11:42:14 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-10-21 11:42:14 -0700 |
| commit | 36aa63b395b0ac1c3cd6e52c4b163c85d015ca6c (patch) | |
| tree | fefb2e6715c62330c828d2c5cd3e081503429fcd /tty | |
| parent | 38ae02a5be03e07f96d50d7c5ff63b3f7634fb68 (diff) | |
| download | patches-36aa63b395b0ac1c3cd6e52c4b163c85d015ca6c.tar.gz | |
more fixes
Diffstat (limited to 'tty')
| -rw-r--r-- | tty/serial8250-ratelimit-too-much-work-error.patch | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/tty/serial8250-ratelimit-too-much-work-error.patch b/tty/serial8250-ratelimit-too-much-work-error.patch new file mode 100644 index 00000000000000..d9be8a8a92cb03 --- /dev/null +++ b/tty/serial8250-ratelimit-too-much-work-error.patch @@ -0,0 +1,50 @@ +From akpm@linux-foundation.org Thu Oct 21 11:39:41 2010 +Message-Id: <201010202300.o9KN0mrG009735@imap1.linux-foundation.org> +Subject: serial8250: ratelimit "too much work" error +To: greg@kroah.com +Cc: akpm@linux-foundation.org, dsd@laptop.org, alan@linux.intel.com +From: Daniel Drake <dsd@laptop.org> +Date: Wed, 20 Oct 2010 16:00:48 -0700 + +From: Daniel Drake <dsd@laptop.org> + +Running a serial console, if too many kernel messages are generated within +a short time causing a lot of serial I/O, the 8250 driver will generate +another kernel message reporting this, which just adds to the I/O. It has +a cascading effect and quickly results the system being brought to its knees +by a flood of "too much work" messages. + +Ratelimit the error message to avoid this. + +[akpm@linux-foundation.org: use the superior printk_ratelimited()] +[akpm@linux-foundation.org: printk_ratelimited() needs ratelimit.h] +Signed-off-by: Daniel Drake <dsd@laptop.org> +Acked-by: Alan Cox <alan@linux.intel.com> +Signed-off-by: Andrew Morton <akpm@linux-foundation.org> +Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> + +--- + drivers/serial/8250.c | 5 +++-- + 1 file changed, 3 insertions(+), 2 deletions(-) + +--- a/drivers/serial/8250.c ++++ b/drivers/serial/8250.c +@@ -31,6 +31,7 @@ + #include <linux/delay.h> + #include <linux/platform_device.h> + #include <linux/tty.h> ++#include <linux/ratelimit.h> + #include <linux/tty_flip.h> + #include <linux/serial_reg.h> + #include <linux/serial_core.h> +@@ -1600,8 +1601,8 @@ static irqreturn_t serial8250_interrupt( + + if (l == i->head && pass_counter++ > PASS_LIMIT) { + /* If we hit this, we're dead. */ +- printk(KERN_ERR "serial8250: too much work for " +- "irq%d\n", irq); ++ printk_ratelimited(KERN_ERR ++ "serial8250: too much work for irq%d\n", irq); + break; + } + } while (l != end); |