4.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: Ard Biesheuvel ard.biesheuvel@linaro.org
commit 6282e916f774e37845c65d1eae9f8c649004f033 upstream.
Due to what appears to be a copy/paste error, the opening ENTRY() of cpu_v7_hvc_switch_mm() lacks a matching ENDPROC(), and instead, the one for cpu_v7_smc_switch_mm() is duplicated.
Given that it is ENDPROC() that emits the Thumb annotation, the cpu_v7_hvc_switch_mm() routine will be called in ARM mode on a Thumb2 kernel, resulting in the following splat:
Internal error: Oops - undefined instruction: 0 [#1] SMP THUMB2 Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.18.0-rc1-00030-g4d28ad89189d-dirty #488 Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 PC is at cpu_v7_hvc_switch_mm+0x12/0x18 LR is at flush_old_exec+0x31b/0x570 pc : [<c0316efe>] lr : [<c04117c7>] psr: 00000013 sp : ee899e50 ip : 00000000 fp : 00000001 r10: eda28f34 r9 : eda31800 r8 : c12470e0 r7 : eda1fc00 r6 : eda53000 r5 : 00000000 r4 : ee88c000 r3 : c0316eec r2 : 00000001 r1 : eda53000 r0 : 6da6c000 Flags: nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
Note the 'ISA ARM' in the last line.
Fix this by using the correct name in ENDPROC().
Cc: stable@vger.kernel.org Fixes: 10115105cb3a ("ARM: spectre-v2: add firmware based hardening") Reviewed-by: Dave Martin Dave.Martin@arm.com Acked-by: Marc Zyngier marc.zyngier@arm.com Signed-off-by: Ard Biesheuvel ard.biesheuvel@linaro.org Signed-off-by: Russell King rmk+kernel@armlinux.org.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/arm/mm/proc-v7.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/arm/mm/proc-v7.S +++ b/arch/arm/mm/proc-v7.S @@ -112,7 +112,7 @@ ENTRY(cpu_v7_hvc_switch_mm) hvc #0 ldmfd sp!, {r0 - r3} b cpu_v7_switch_mm -ENDPROC(cpu_v7_smc_switch_mm) +ENDPROC(cpu_v7_hvc_switch_mm) #endif ENTRY(cpu_v7_iciallu_switch_mm) mov r3, #0