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SubjectRe: [PATCH] x86/mm: Do not warn about PCI BIOS W+X mappings
On Mon, Oct 08, 2018 at 09:53:48PM +0200, Thomas Gleixner wrote:
> PCI BIOS requires the BIOS area 0x0A0000-0x0FFFFFF to be mapped W+X for
> various legacy reasons. When CONFIG_DEBUG_WX is enabled, this triggers the
> WX warning, but this is misleading because the mapping is required and is
> not a result of an accidental oversight.
>
> Prevent the full warning when PCI BIOS is enabled and the detected WX
> mapping is in the BIOS area. Just emit a pr_warn() which denotes the
> fact. This is partially duplicating the info which the PCI BIOS code emits
> when it maps the area as executable, but that info is not in the context of
> the WX checking output.
>
> Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Cc: Joerg Roedel <joro@8bytes.org>
> Cc: Kees Cook <keescook@chromium.org>
> Cc: Bjorn Helgaas <bhelgaas@google.com>

Tested-by: Borislav Petkov <bp@suse.de>

--
Regards/Gruss,
Boris.

Good mailing practices for 400: avoid top-posting and trim the reply.

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