linux-sg2042/arch
Eric W. Biederman 45c9953325 [PATCH] Use delayed disable mode of ioapic edge triggered interrupts
Komuro reports that ISA interrupts do not work after a disable_irq(),
causing some PCMCIA drivers to not work, with messages like

	eth0: Asix AX88190: io 0x300, irq 3, hw_addr xx:xx:xx:xx:xx:xx
	eth0: found link beat
	eth0: autonegotiation complete: 100baseT-FD selected
	eth0: interrupt(s) dropped!
	eth0: interrupt(s) dropped!
	eth0: interrupt(s) dropped!
	...

Linus Torvalds <torvalds@osdl.org> said:

  "Now, edge-triggered interrupts are a _lot_ harder to mask, because the
   Intel APIC is an unbelievable piece of sh*t, and has the edge-detect logic
   _before_ the mask logic, so if a edge happens _while_ the device is
   masked, you'll never ever see the edge ever again (unmasking will not
   cause a new edge, so you simply lost the interrupt).

   So when you "mask" an edge-triggered IRQ, you can't really mask it at all,
   because if you did that, you'd lose it forever if the IRQ comes in while
   you masked it. Instead, we're supposed to leave it active, and set a flag,
   and IF the IRQ comes in, we just remember it, and mask it at that point
   instead, and then on unmasking, we have to replay it by sending a
   self-IPI."

This trivial patch solves the problem.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@redhat.com>
Acked-by: Komuro <komurojun-mbn@nifty.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-15 09:04:32 -08:00
..
alpha Update for the srm_env driver. 2006-11-07 23:50:37 +01:00
arm [ARM] 3927/1: Allow show_mem() to work with holes in memory map. 2006-11-07 19:39:00 +00:00
arm26 [PATCH] remove bogus arch-specific syscall exports 2006-10-11 11:17:07 -07:00
avr32 AVR32: Add missing return instruction in __raw_writesb 2006-11-06 14:07:16 +01:00
cris [PATCH] cryptocop: double spin_lock_irqsave() 2006-10-30 12:08:41 -08:00
frv [PATCH] vmlinux.lds: consolidate initcall sections 2006-10-27 15:34:51 -07:00
h8300 [PATCH] vmlinux.lds: consolidate initcall sections 2006-10-27 15:34:51 -07:00
i386 [PATCH] Use delayed disable mode of ioapic edge triggered interrupts 2006-11-15 09:04:32 -08:00
ia64 [PATCH] hugetlb: prepare_hugepage_range check offset too 2006-11-14 09:09:27 -08:00
m32r [PATCH] vmlinux.lds: consolidate initcall sections 2006-10-27 15:34:51 -07:00
m68k [PATCH] m68k: consolidate initcall sections 2006-10-29 12:07:41 -08:00
m68knommu [PATCH] vmlinux.lds: consolidate initcall sections 2006-10-27 15:34:51 -07:00
mips [MIPS] Fix EV64120 and Ocelot builds by providing a plat_timer_setup(). 2006-11-06 20:55:39 +00:00
parisc [PATCH] vmlinux.lds: consolidate initcall sections 2006-10-27 15:34:51 -07:00
powerpc [PATCH] hugetlb: prepare_hugepage_range check offset too 2006-11-14 09:09:27 -08:00
ppc [POWERPC] Make alignment exception always check exception table 2006-11-01 15:16:04 +11:00
s390 [S390] IRQs too early enabled. 2006-11-06 10:49:02 +01:00
sh sh: Titan defconfig update. 2006-10-31 12:53:29 +09:00
sh64 [PATCH] vmlinux.lds: consolidate initcall sections 2006-10-27 15:34:51 -07:00
sparc [SPARC]: Fix robust futex syscalls and wire up migrate_pages. 2006-11-05 16:51:03 -08:00
sparc64 [SPARC]: Fix robust futex syscalls and wire up migrate_pages. 2006-11-05 16:51:03 -08:00
um [PATCH] uml: include tidying 2006-11-03 12:27:59 -08:00
v850 [PATCH] vmlinux.lds: consolidate initcall sections 2006-10-27 15:34:51 -07:00
x86_64 [PATCH] Use delayed disable mode of ioapic edge triggered interrupts 2006-11-15 09:04:32 -08:00
xtensa [PATCH] vmlinux.lds: consolidate initcall sections 2006-10-27 15:34:51 -07:00