[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] [PATCH 4/4] arm: traps: handle SMC32 in check_conditional_instr()



Hi,

On 07/28/2017 08:43 PM, Volodymyr Babchuk wrote:
On ARMv8 architecture SMC instruction in aarch32 state can be conditional.

version + paragraph please.

Also, ARMv8 supports both AArch32 and AArch64. As I said in my answer on "arm: smccc: handle SMCs/HVCs according to SMCCC" ([1]), This field exists for both architecture. I really don't want to tie the 32-bit port to ARMv7. We should be able to use ARMv8 too.

Thus, we should not skip it while checking HSR.EC value. >
For this type of exception special coding of HSR.ISS is used. There is
additional flag to check before perfoming standart handling of CCVALID

performing standard

and COND fields.

Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk@xxxxxxxx>
---
  xen/arch/arm/traps.c | 12 ++++++++++++
  1 file changed, 12 insertions(+)

diff --git a/xen/arch/arm/traps.c b/xen/arch/arm/traps.c
index eae2212..6a21763 100644
--- a/xen/arch/arm/traps.c
+++ b/xen/arch/arm/traps.c
@@ -1717,8 +1717,20 @@ static int check_conditional_instr(struct cpu_user_regs 
*regs,
      int cond;
/* Unconditional Exception classes */
+#ifdef CONFIG_ARM_32
      if ( hsr.ec == HSR_EC_UNKNOWN || hsr.ec >= 0x10 )
          return 1;
+#else
+    if ( hsr.ec == HSR_EC_UNKNOWN || (hsr.ec >= 0x10 && hsr.ec != 
HSR_EC_SMC32))
+        return 1;
+
+    /*
+     * Special case for SMC32: we need to check CCKNOWNPASS before
+     * checking CCVALID

Missing full stop.

+     */
+    if (hsr.ec == HSR_EC_SMC32 && hsr.cond.ccknownpass == 0)
+        return 1;
+#endif
/* Check for valid condition in hsr */
      cond = hsr.cond.ccvalid ? hsr.cond.cc : -1;


Cheers,

[1] https://lists.xen.org/archives/html/xen-devel/2017-07/msg01671.html";

--
Julien Grall

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel

 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.