The 32-bit x86 PAT code uses __set_pmd_pte() to update pmds.
This uses pgd_list currently, but we don't need the global
list as we can walk the task list under RCU.
(This code already holds the pgd_lock.)
Cc: Andrew Morton <a...@linux-foundation.org>
Cc: Andy Lutomirski <l...@amacapital.net>
Cc: Borislav Petkov <b...@alien8.de>
Cc: Brian Gerst <brge...@gmail.com>
Cc: Denys Vlasenko <dvlas...@redhat.com>
Cc: H. Peter Anvin <h...@zytor.com>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Rik van Riel <r...@redhat.com>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Waiman Long <waiman.l...@hp.com>
Cc: linux...@vger.kernel.org
Signed-off-by: Ingo Molnar <mi...@kernel.org>
---
arch/x86/mm/pageattr.c | 19 ++++++++++++++++---
1 file changed, 16 insertions(+), 3 deletions(-)
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 997fc97e9072..93c134fdb398 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -438,18 +438,31 @@ static void __set_pmd_pte(pte_t *kpte, unsigned long
address, pte_t pte)
set_pte_atomic(kpte, pte);
#ifdef CONFIG_X86_32
if (!SHARED_KERNEL_PMD) {
- struct page *page;
+ struct task_struct *g, *p;
- list_for_each_entry(page, &pgd_list, lru) {
+ rcu_read_lock();
+
+ for_each_process_thread(g, p) {
+ spinlock_t *pgt_lock;
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
- pgd = (pgd_t *)page_address(page) + pgd_index(address);
+ if (!p->mm)
+ continue;
+
+ pgt_lock = &p->mm->page_table_lock;
+ spin_lock(pgt_lock);
+
+ pgd = p->mm->pgd + pgd_index(address);
pud = pud_offset(pgd, address);
pmd = pmd_offset(pud, address);
set_pte_atomic((pte_t *)pmd, pte);
+
+ spin_unlock(pgt_lock);
}
+
+ rcu_read_unlock();
}
#endif
}
--
2.1.4
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
