commit 6282e916 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: 10115105 ("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>