Re: [PATCH] powerpc/mm/hash: Improve address limit checks

Michael Ellerman [off-list ref] writes:

On Thu, 2019-05-16 at 11:50:54 UTC, "Aneesh Kumar K.V" wrote:

quoted

Different parts of the code do the limit check by ignoring the top nibble
of EA. ie. we do checks like

	if ((ea & EA_MASK)  >= H_PGTABLE_RANGE)
	   	error

This patch makes sure we don't insert SLB entries for addresses whose top nibble
doesn't match the ignored bits.

With an address like 0x4000000008000000, we can result in wrong slb entries like

13 4000000008000000 400ea1b217000510   1T ESID=   400000 VSID=   ea1b217000 LLP:110

without this patch we will map that EA with LINEAR_MAP_REGION_ID and further
those addr limit check will return false.

Signed-off-by: Aneesh Kumar K.V <redacted>

Applied to powerpc fixes, thanks.

https://git.kernel.org/powerpc/c/c179976cf4cbd2e65f29741d5bc07ccf

Actually this patch was superseeded. This should have been a reply to:

  https://lore.kernel.org/linuxppc-dev/20190517132958.22299-1-mpe@ellerman.id.au/ (local)

cheers