kernel_samsung_sm7125

jenna

History

Russ Anderson c642b8391c __do_IRQ does not check IRQ_DISABLED when IRQ_PER_CPU is set In __do_IRQ(), the normal case is that IRQ_DISABLED is checked and if set the handler (handle_IRQ_event()) is not called. Earlier in __do_IRQ(), if IRQ_PER_CPU is set the code does not check IRQ_DISABLED and calls the handler even though IRQ_DISABLED is set. This behavior seems unintentional. One user encountering this behavior is the CPE handler (in arch/ia64/kernel/mca.c). When the CPE handler encounters too many CPEs (such as a solid single bit error), it sets up a polling timer and disables the CPE interrupt (to avoid excessive overhead logging the stream of single bit errors). disable_irq_nosync() is called which sets IRQ_DISABLED. The IRQ_PER_CPU flag was previously set (in ia64_mca_late_init()). The net result is the CPE handler gets called even though it is marked disabled. If the behavior of not checking IRQ_DISABLED when IRQ_PER_CPU is set is intentional, it would be worthy of a comment describing the intended behavior. disable_irq_nosync() does call chip->disable() to provide a chipset specifiec interface for disabling the interrupt, which avoids this issue when used. Signed-off-by: Russ Anderson <rja@sgi.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		17 years ago
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Makefile	…
autoprobe.c	…
chip.c	Compile handle_percpu_irq even for uniprocessor kernels	18 years ago
devres.c	rip some includes from linux/interrupt.h	18 years ago
handle.c	__do_IRQ does not check IRQ_DISABLED when IRQ_PER_CPU is set	17 years ago
internals.h	…
manage.c	Fix synchronize_irq races with IRQ handler	18 years ago
migration.c	…
proc.c	…
resend.c	genirq: suppress resend of level interrupts	18 years ago
spurious.c	…