From 5e427ec2d066b48a5c27b3a5a3315f7e4e729077 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Mon, 20 May 2013 11:36:03 -0700 Subject: [PATCH] x86: Fix bit corruption at CPU resume time MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit In commit 78d77df71510 ("x86-64, init: Do not set NX bits on non-NX capable hardware") we added the early_pmd_flags that gets the NX bit set when a CPU supports NX. However, the new variable was marked __initdata, because the main _use_ of this is in an __init routine. However, the bit setting happens from secondary_startup_64(), which is called not only at bootup, but on every secondary CPU start. Including resuming from STR and at CPU hotplug time. So the value cannot be __initdata. Reported-bisected-and-tested-by: Michal Hocko Cc: stable@vger.kernel.org # v3.9 Acked-by: Peter Anvin Cc: Fernando Luis Vázquez Cao Signed-off-by: Linus Torvalds --- arch/x86/kernel/head64.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index dab95a85f7f8..55b67614ed94 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -34,7 +34,7 @@ extern pgd_t early_level4_pgt[PTRS_PER_PGD]; extern pmd_t early_dynamic_pgts[EARLY_DYNAMIC_PAGE_TABLES][PTRS_PER_PMD]; static unsigned int __initdata next_early_pgt = 2; -pmdval_t __initdata early_pmd_flags = __PAGE_KERNEL_LARGE & ~(_PAGE_GLOBAL | _PAGE_NX); +pmdval_t early_pmd_flags = __PAGE_KERNEL_LARGE & ~(_PAGE_GLOBAL | _PAGE_NX); /* Wipe all early page tables except for the kernel symbol map */ static void __init reset_early_page_tables(void) -- 2.20.1