4.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
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@xxxxxxxxxxxxxxx> #v4.14
Reported-by: Nicolas Dechesne <nicolas.dechesne@xxxxxxxxxx>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
Acked-by: Will Deacon <will.deacon@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/arm64/mm/proc.S | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- 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
isb
tlbi vmalle1
dsb nsh