x86: expand irq-off region in text_poke()

Expand irq-off region to cover fixmap using code and cache synchronizing.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
LKML-Reference: <49B54688.8090403@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index 2d903b7..f576587 100644 (file)
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -526,13 +526,12 @@ void *__kprobes text_poke(void *addr, const void *opcode, size_t len)
                pages[1] = virt_to_page(addr + PAGE_SIZE);
        }
        BUG_ON(!pages[0]);
+       local_irq_save(flags);
        set_fixmap(FIX_TEXT_POKE0, page_to_phys(pages[0]));
        if (pages[1])
                set_fixmap(FIX_TEXT_POKE1, page_to_phys(pages[1]));
        vaddr = (char *)fix_to_virt(FIX_TEXT_POKE0);
-       local_irq_save(flags);
        memcpy(&vaddr[(unsigned long)addr & ~PAGE_MASK], opcode, len);
-       local_irq_restore(flags);
        clear_fixmap(FIX_TEXT_POKE0);
        if (pages[1])
                clear_fixmap(FIX_TEXT_POKE1);
@@ -542,5 +541,6 @@ void *__kprobes text_poke(void *addr, const void *opcode, size_t len)
           that causes hangs on some VIA CPUs. */
        for (i = 0; i < len; i++)
                BUG_ON(((char *)addr)[i] != ((char *)opcode)[i]);
+       local_irq_restore(flags);
        return addr;
 }