diff mbox

[3.16.y-ckt,061/126] MIPS: KVM: Fix CACHE immediate offset sign extension

Message ID 1452076655-12851-62-git-send-email-luis.henriques@canonical.com (mailing list archive)
State New, archived
Headers show

Commit Message

Luis Henriques Jan. 6, 2016, 10:36 a.m. UTC 
3.16.7-ckt22 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: James Hogan <james.hogan@imgtec.com>

commit c5c2a3b998f1ff5a586f9d37e154070b8d550d17 upstream.

The immediate field of the CACHE instruction is signed, so ensure that
it gets sign extended by casting it to an int16_t rather than just
masking the low 16 bits.

Fixes: e685c689f3a8 ("KVM/MIPS32: Privileged instruction/target branch emulation.")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[ luis: backported to 3.16:
  - file rename: emulate.c -> kvm_mips_emul.c ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
---
 arch/mips/kvm/kvm_mips_emul.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
diff mbox

Patch

diff --git a/arch/mips/kvm/kvm_mips_emul.c b/arch/mips/kvm/kvm_mips_emul.c
index 18b4e2fdae33..950229176c2f 100644
--- a/arch/mips/kvm/kvm_mips_emul.c
+++ b/arch/mips/kvm/kvm_mips_emul.c
@@ -1434,7 +1434,7 @@  kvm_mips_emulate_cache(uint32_t inst, uint32_t *opc, uint32_t cause,
 
 	base = (inst >> 21) & 0x1f;
 	op_inst = (inst >> 16) & 0x1f;
-	offset = inst & 0xffff;
+	offset = (int16_t)inst;
 	cache = (inst >> 16) & 0x3;
 	op = (inst >> 18) & 0x7;