linux-toradex.git/kernel, branch v2.6.18

[PATCH] genirq core: fix handle_level_irq()

2006-09-19T14:57:20+00:00

while porting the -rt tree to 2.6.18-rc7 i noticed the following
screaming-IRQ scenario on an SMP system:

 2274  0Dn.:1 0.001ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)
 2274  0Dn.:1 0.010ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)
 2274  0Dn.:1 0.020ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)
 2274  0Dn.:1 0.029ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)
 2274  0Dn.:1 0.039ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)
 2274  0Dn.:1 0.048ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)
 2274  0Dn.:1 0.058ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)
 2274  0Dn.:1 0.068ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)
 2274  0Dn.:1 0.077ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)
 2274  0Dn.:1 0.087ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)
 2274  0Dn.:1 0.097ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)

as it turns out, the bug is caused by handle_level_irq(), which if it
races with another CPU already handling this IRQ, it _unmasks_ the IRQ
line on the way out. This is not how 2.6.17 works, and we introduced
this bug in one of the early genirq cleanups right before it went into
-mm. (the bug was not in the genirq patchset for a long time, and we
didnt notice the bug due to the lack of -rt rebase to the new genirq
code. -rt, and hardirq-preemption in particular opens up such races much
wider than anything else.)

Signed-off-by: Ingo Molnar 
Signed-off-by: Thomas Gleixner 
Acked-by: Benjamin Herrenschmidt 
Signed-off-by: Linus Torvalds

[PATCH] bug fix in kernel/kmod.c

2006-09-16T19:54:32+00:00

I think there is a bug in kmod.c: In __call_usermodehelper(), when
kernel_thread(wait_for_helper, ...) return success, since wait_for_helper()
might call complete() at any time, the sub_info should not be used any
more.

Normally wait_for_helper() take a long time to finish, you may not get
problem for most of the case.  But if you remove /sbin/modprobe, it may
become easier for you to get a oop in khelper.

Cc: Matt Helsley 
Cc: Martin Schwidefsky 
Cc: Arnd Bergmann 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] genirq: fix typo in IRQ resend

2006-09-16T19:54:30+00:00

Fix a bug where the IRQ_PENDING flag is never cleared and the ISR is called
endlessly without an actual interrupt.

Signed-off-by: Imre Deak 
Acked-by: Thomas Gleixner 
Acked-by: Ingo Molnar 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] rcu_do_batch: make ->qlen decrement irq safe

2006-09-13T14:32:14+00:00

rcu_do_batch() decrements rdp->qlen with irqs enabled.  This is not good,
it can also be modified by call_rcu() from interrupt.

Decrement ->qlen once with irqs disabled, after a main loop.

Signed-off-by: Oleg Nesterov 
Cc: Dipankar Sarma 
Cc: "Paul E. McKenney" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] lockdep: double the number of stack-trace entries

2006-09-13T14:32:14+00:00

Miles Lane reported the "BUG: MAX_STACK_TRACE_ENTRIES too low!" message,
which means that during normal use his system produced enough lockdep
events so that the 128-thousand entries stack-trace array got exhausted.
Double the size of the array.

Signed-off-by: Ingo Molnar 
Cc: Miles Lane 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] audit: AUDIT_PERM support

2006-09-11T17:32:30+00:00

add support for AUDIT_PERM predicate

Signed-off-by: Al Viro

[PATCH] update audit rule change messages

2006-09-11T17:32:17+00:00

Make the audit message for implicit rule removal more informative.
Make the rule update message consistent with other messages.

Signed-off-by: Amy Griffis 
Signed-off-by: Al Viro

[PATCH] sanity check audit_buffer

2006-09-11T17:32:17+00:00

Add sanity checks for NULL audit_buffer consistent with other
audit_log* routines.

Signed-off-by: Amy Griffis 
Signed-off-by: Al Viro

[PATCH] fix ppid bug in 2.6.18 kernel

2006-09-11T17:32:04+00:00

Hello,

During some troubleshooting, I found that ppid was accidentally omitted from
the legacy rule section. This resulted in EINVAL for any rule with ppid sent
with AUDIT_ADD.

Signed-off-by: Steve Grubb 
Signed-off-by: Al Viro

[PATCH] Use the correct restart option for futex_lock_pi

2006-09-08T17:22:50+00:00

The current implementation of futex_lock_pi returns -ERESTART_RESTARTBLOCK
in case that the lock operation has been interrupted by a signal.  This
results in a return of -EINTR to userspace in case there is an handler for
the signal.  This is wrong, because userspace expects that the lock
function does not return in any case of signal delivery.

This was not caught by my insufficient test case, but triggered a nasty
userspace problem in an high load application scenario.  Unfortunately also
glibc does not check for this invalid return value.

Using -ERSTARTNOINTR makes sure, that the interrupted syscall is restarted.
 The restart block related code can be safely removed, as the possible
timeout argument is an absolute time value.

Signed-off-by: Thomas Gleixner 
Acked-by: Ingo Molnar 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds