From 5289f46b9de04bde181d833d48df9671b69c4b08 Mon Sep 17 00:00:00 2001 From: Kyle McMartin Date: Tue, 23 Dec 2008 08:44:30 -0500 Subject: [PATCH] parisc: disable UP-optimized flush_tlb_mm flush_tlb_mm's "optimized" uniprocessor case of allocating a new context for userspace is exposing a race where we can suddely return to a syscall with the protection id and space id out of sync, trapping on the next userspace access. Debugged-by: James Bottomley Tested-by: Helge Deller Signed-off-by: Kyle McMartin Signed-off-by: Linus Torvalds --- arch/parisc/include/asm/tlbflush.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/parisc/include/asm/tlbflush.h b/arch/parisc/include/asm/tlbflush.h index b72ec66db699..1f6fd4fc05b9 100644 --- a/arch/parisc/include/asm/tlbflush.h +++ b/arch/parisc/include/asm/tlbflush.h @@ -44,9 +44,12 @@ static inline void flush_tlb_mm(struct mm_struct *mm) { BUG_ON(mm == &init_mm); /* Should never happen */ -#ifdef CONFIG_SMP +#if 1 || defined(CONFIG_SMP) flush_tlb_all(); #else + /* FIXME: currently broken, causing space id and protection ids + * to go out of sync, resulting in faults on userspace accesses. + */ if (mm) { if (mm->context != 0) free_sid(mm->context); -- 2.39.2