On Fri, Feb 23, 2018 at 06:29:02PM +0000, Ard Biesheuvel wrote:
Stable backport commit 173358a49173 ("arm64: kpti: Add ->enable callback to remap swapper using nG mappings") of upstream commit f992b4dfd58b did not survive the backporting process unscathed, and ends up writing garbage into the TTBR1_EL1 register, rather than pointing it to the zero page to disable translations. Fix that.
Cc: stable@vger.kernel.org #v4.14 Reported-by: Nicolas Dechesne nicolas.dechesne@linaro.org Signed-off-by: Ard Biesheuvel ard.biesheuvel@linaro.org
arch/arm64/mm/proc.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
Any reason why you didn't cc: the stable list, as this is a patch that is not needed in mainline, right?
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index 08572f95bd8a..2b473ddeb7a3 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -155,7 +155,7 @@ ENDPROC(cpu_do_switch_mm) .macro __idmap_cpu_set_reserved_ttbr1, tmp1, tmp2 adrp \tmp1, empty_zero_page
- msr ttbr1_el1, \tmp2
- msr ttbr1_el1, \tmp1
I don't understand why this isn't also needed in Linus's tree. What commit there prevents this from being required?
thanks,
greg k-h