The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 827a108e354db633698f0b4a10c1ffd2b1f8d1d0 Mon Sep 17 00:00:00 2001

From: Jean-Philippe Brucker jean-philippe.brucker@arm.com Date: Mon, 8 Apr 2019 18:17:19 +0100 Subject: [PATCH] arm64: Save and restore OSDLR_EL1 across suspend/resume

When the CPU comes out of suspend, the firmware may have modified the OS Double Lock Register. Save it in an unused slot of cpu_suspend_ctx, and restore it on resume.

Cc: stable@vger.kernel.org Signed-off-by: Jean-Philippe Brucker jean-philippe.brucker@arm.com Signed-off-by: Will Deacon will.deacon@arm.com

diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index aa0817c9c4c3..fdd626d34274 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -65,24 +65,25 @@ ENTRY(cpu_do_suspend) mrs x2, tpidr_el0 mrs x3, tpidrro_el0 mrs x4, contextidr_el1 - mrs x5, cpacr_el1 - mrs x6, tcr_el1 - mrs x7, vbar_el1 - mrs x8, mdscr_el1 - mrs x9, oslsr_el1 - mrs x10, sctlr_el1 + mrs x5, osdlr_el1 + mrs x6, cpacr_el1 + mrs x7, tcr_el1 + mrs x8, vbar_el1 + mrs x9, mdscr_el1 + mrs x10, oslsr_el1 + mrs x11, sctlr_el1 alternative_if_not ARM64_HAS_VIRT_HOST_EXTN - mrs x11, tpidr_el1 + mrs x12, tpidr_el1 alternative_else - mrs x11, tpidr_el2 + mrs x12, tpidr_el2 alternative_endif - mrs x12, sp_el0 + mrs x13, sp_el0 stp x2, x3, [x0] - stp x4, xzr, [x0, #16] - stp x5, x6, [x0, #32] - stp x7, x8, [x0, #48] - stp x9, x10, [x0, #64] - stp x11, x12, [x0, #80] + stp x4, x5, [x0, #16] + stp x6, x7, [x0, #32] + stp x8, x9, [x0, #48] + stp x10, x11, [x0, #64] + stp x12, x13, [x0, #80] ret ENDPROC(cpu_do_suspend)

@@ -105,8 +106,8 @@ ENTRY(cpu_do_resume) msr cpacr_el1, x6

/* Don't change t0sz here, mask those bits when restoring */ - mrs x5, tcr_el1 - bfi x8, x5, TCR_T0SZ_OFFSET, TCR_TxSZ_WIDTH + mrs x7, tcr_el1 + bfi x8, x7, TCR_T0SZ_OFFSET, TCR_TxSZ_WIDTH

msr tcr_el1, x8 msr vbar_el1, x9 @@ -130,6 +131,7 @@ alternative_endif /* * Restore oslsr_el1 by writing oslar_el1 */ + msr osdlr_el1, x5 ubfx x11, x11, #1, #1 msr oslar_el1, x11 reset_pmuserenr_el0 x0 // Disable PMU access from EL0