Ingo Molnar 9a24d04a3c x86: fix global_flush_tlb() bug ... While we were reviewing pageattr_32/64.c for unification, Thomas Gleixner noticed the following serious SMP bug in global_flush_tlb(): down_read(&init_mm.mmap_sem); list_replace_init(&deferred_pages, &l); up_read(&init_mm.mmap_sem); this is SMP-unsafe because list_replace_init() done on two CPUs in parallel can corrupt the list. This bug has been introduced about a year ago in the 64-bit tree: commit ea7322decb Author: Andi Kleen <ak@suse.de> Date: Thu Dec 7 02:14:05 2006 +0100 [PATCH] x86-64: Speed and clean up cache flushing in change_page_attr down_read(&init_mm.mmap_sem); - dpage = xchg(&deferred_pages, NULL); + list_replace_init(&deferred_pages, &l); up_read(&init_mm.mmap_sem); the xchg() based version was SMP-safe, but list_replace_init() is not. So this "cleanup" introduced a nasty bug. why this bug never become prominent is a mystery - it can probably be explained with the (still) relative obscurity of the x86_64 architecture. the safe fix for now is to write-lock init_mm.mmap_sem. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>		2007-10-19 12:19:26 +02:00
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boot	[x86] remove uses of magic macros for boot_params access	2007-10-16 17:38:31 -07:00
crypto	x86_64: move crypto	2007-10-11 11:17:03 +02:00
ia32	sysctl: x86_64 remove unnecessary binary paths	2007-10-18 14:37:22 -07:00
kernel	sparse pointer use of zero as null	2007-10-18 14:37:31 -07:00
lib	x86: rename .i assembler includes to .h	2007-10-17 20:16:29 +02:00
mach-default	x86: clean up struct irqaction initializers	2007-10-17 20:16:06 +02:00
mach-es7000	i386: es7000 minor cleanups	2007-10-17 20:16:15 +02:00
mach-generic	i386: make struct apic_probe static	2007-10-17 20:15:54 +02:00
mach-visws	[x86] remove uses of magic macros for boot_params access	2007-10-16 17:38:31 -07:00
mach-voyager	x86: expand /proc/interrupts to include missing vectors, v2	2007-10-17 20:16:53 +02:00
math-emu	kbuild: fix up CFLAGS usage	2007-10-14 21:49:42 +02:00
mm	x86: fix global_flush_tlb() bug	2007-10-19 12:19:26 +02:00
oprofile	i386: make Oprofile call shutdown() only once per session	2007-10-17 20:15:14 +02:00
pci	x86: pci use pci=bfsort for HP DL385 G2 and DL585 G2	2007-10-17 20:15:46 +02:00
power	i386: move power	2007-10-11 11:16:34 +02:00
vdso	x86: vdso linker script cleanup	2007-10-17 20:17:06 +02:00
video	i386: move video	2007-10-11 11:16:56 +02:00
xen	Merge ssh://master.kernel.org/pub/scm/linux/kernel/git/tglx/linux-2.6-x86	2007-10-17 13:13:16 -07:00