Re: 4.4-rc5: ugly warn on: 5 W+X pages found

Pavel Machek
2015-12-15T22:07:14Z

On Tue 2015-12-15 22:33:59, Borislav Petkov wrote:
> On Tue, Dec 15, 2015 at 09:58:35PM +0100, Pavel Machek wrote:
> > [ 0.000000] Base memory trampoline at [c009b000] 9b000 size 16384
> > [ 0.000000] ------------[ cut here ]------------
> > [ 0.000000] WARNING: CPU: 0 PID: 0 at
> > ./arch/x86/include/asm/pgtable.h:357 kernel_physical_mapping_init+0x
> > 256/0x395()
> > [ 0.000000] Modules linked in:
> > [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.4.0-rc5+ #137
> > [ 0.000000] Hardware name: LENOVO 17097HU/17097HU, BIOS 7BETD8WW
> > (2.19 ) 03/31/2011
> > [ 0.000000] 00000000 00000000 c4e63e90 c42baaf8 00000000 c4e63eac
> > c404066b 00000165
> > [ 0.000000] c4f134da 00000000 00000000 00000000 c4e63ebc c404070f
> > 00000009 00000000
> > [ 0.000000] c4e63f18 c4f134da c4e63f00 00000000 00000000 00000000
> > 00000000 00000000
> > [ 0.000000] Call Trace:
> > [ 0.000000] [<c42baaf8>] dump_stack+0x41/0x59
> > [ 0.000000] [<c404066b>] warn_slowpath_common+0x6b/0xa0
> > [ 0.000000] [<c4f134da>] ?
> > kernel_physical_mapping_init+0x256/0x395
> > [ 0.000000] [<c404070f>] warn_slowpath_null+0xf/0x20
> > [ 0.000000] [<c4f134da>] kernel_physical_mapping_init+0x256/0x395
> > [ 0.000000] [<c4a4de21>] init_memory_mapping+0x191/0x300
> > [ 0.000000] [<c4f12d96>] init_mem_mapping+0xe7/0x1f3
>
> Looks like the ISA range to me:
>
> init_mem_mapping:
>
> ...
>
> /* the ISA range is always mapped regardless of memory holes */
> init_memory_mapping(0, ISA_END_ADDRESS);
>
> Does that kernel_physical_mapping_init() even pay attention to
> __supported_pte_mask and thus _PAGE_NX? I don't see it.

Mystery solved, and prize goes to the lguest.

Pavel
--
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