@@ -12,11 +12,10 @@
#include <linux/bitops.h>
#include <linux/spinlock.h>
+#include <linux/mm_types.h>
#include <asm/processor.h>
#include <asm/cache.h>
-struct vm_area_struct;
-
/*
* kern_addr_valid(ADDR) tests if ADDR is pointing to valid kernel
* memory. For the return value to be meaningful, ADDR must be >=
@@ -40,7 +39,14 @@ struct vm_area_struct;
do{ \
*(pteptr) = (pteval); \
} while(0)
-#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
+
+extern void purge_tlb_entries(struct mm_struct *, unsigned long);
+
+#define set_pte_at(mm, addr, ptep, pteval) \
+ do { \
+ set_pte(ptep, pteval); \
+ purge_tlb_entries(mm, addr); \
+ } while (0)
#endif /* !__ASSEMBLY__ */
@@ -466,6 +472,7 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr,
old = pte_val(*ptep);
new = pte_val(pte_wrprotect(__pte (old)));
} while (cmpxchg((unsigned long *) ptep, old, new) != old);
+ purge_tlb_entries(mm, addr);
#else
pte_t old_pte = *ptep;
set_pte_at(mm, addr, ptep, pte_wrprotect(old_pte));
@@ -420,6 +420,24 @@ void kunmap_parisc(void *addr)
EXPORT_SYMBOL(kunmap_parisc);
#endif
+void purge_tlb_entries(struct mm_struct *mm, unsigned long addr)
+{
+ unsigned long flags;
+
+ /* Note: purge_tlb_entries can be called at startup with
+ no context. */
+
+ /* Disable preemption while we play with %sr1. */
+ preempt_disable();
+ mtsp(mm->context, 1);
+ purge_tlb_start(flags);
+ pdtlb(addr);
+ pitlb(addr);
+ purge_tlb_end(flags);
+ preempt_enable();
+}
+EXPORT_SYMBOL(purge_tlb_entries);
+
void __flush_tlb_range(unsigned long sid, unsigned long start,
unsigned long end)
{
This is a note to let you know that I have just added a patch titled Purge existing TLB entries in set_pte_at and to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.5.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From 2d65a71d04475edf0fac5fca580496639ded46e1 Mon Sep 17 00:00:00 2001 From: John David Anglin <dave.anglin@bell.net> Date: Mon, 14 Jan 2013 19:45:00 -0500 Subject: [PATCH] Purge existing TLB entries in set_pte_at and ptep_set_wrprotect MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit commit 7139bc1579901b53db7e898789e916ee2fb52d78 upstream. This patch goes a long way toward fixing the minifail bug, and it significantly improves the stability of SMP machines such as the rp3440. When write protecting a page for COW, we need to purge the existing translation. Otherwise, the COW break doesn't occur as expected because the TLB may still have a stale entry which allows writes. [jejb: fix up checkpatch errors] Signed-off-by: John David Anglin <dave.anglin@bell.net> Signed-off-by: James Bottomley <JBottomley@Parallels.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- arch/parisc/include/asm/pgtable.h | 13 ++++++++++--- arch/parisc/kernel/cache.c | 18 ++++++++++++++++++ 2 files changed, 28 insertions(+), 3 deletions(-) -- 1.8.1.2