[ Upstream commit 510bb96fe5b3480b4b22d815786377e54cb701e7 ] Xose Vazquez Perez reported boot warnings when NX is disabled on the kernel command line. __early_set_fixmap() triggers this warning: attempted to set unsupported pgprot: 8000000000000163 bits: 8000000000000000 supported: 7fffffffffffffff WARNING: CPU: 0 PID: 0 at arch/x86/include/asm/pgtable.h:537 __early_set_fixmap+0xa2/0xff because it uses __default_kernel_pte_mask to mask out unsupported bits. Use __supported_pte_mask instead. Disabling NX on the command line also triggers the NX warning in the page table mapping check: WARNING: CPU: 1 PID: 1 at arch/x86/mm/dump_pagetables.c:262 note_page+0x2ae/0x650 .... Make the warning depend on NX set in __supported_pte_mask. Reported-by: Xose Vazquez Perez <xose.vazquez@xxxxxxxxx> Tested-by: Xose Vazquez Perez <xose.vazquez@xxxxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: H. Peter Anvin <hpa@xxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Rik van Riel <riel@xxxxxxxxxxx> Link: http://lkml.kernel.org/r/alpine.DEB.2.21.1904151037530.1729@xxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- arch/x86/mm/dump_pagetables.c | 3 ++- arch/x86/mm/ioremap.c | 2 +- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c index e3cdc85ce5b6e..84304626b1cb8 100644 --- a/arch/x86/mm/dump_pagetables.c +++ b/arch/x86/mm/dump_pagetables.c @@ -259,7 +259,8 @@ static void note_wx(struct pg_state *st) #endif /* Account the WX pages */ st->wx_pages += npages; - WARN_ONCE(1, "x86/mm: Found insecure W+X mapping at address %pS\n", + WARN_ONCE(__supported_pte_mask & _PAGE_NX, + "x86/mm: Found insecure W+X mapping at address %pS\n", (void *)st->start_address); } diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index 5378d10f1d31d..3b76fe954978c 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -825,7 +825,7 @@ void __init __early_set_fixmap(enum fixed_addresses idx, pte = early_ioremap_pte(addr); /* Sanitize 'prot' against any unsupported bits: */ - pgprot_val(flags) &= __default_kernel_pte_mask; + pgprot_val(flags) &= __supported_pte_mask; if (pgprot_val(flags)) set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, flags)); -- 2.20.1
