[Xen-devel] [RFC v2 1/6] xen/arm: traps: Reorder early overwrite of FID

["Edgar E. Iglesias" <edgar.iglesias@xxxxxxxxx>]

From: "Edgar E. Iglesias" <edgar.iglesias@xxxxxxxxxx>

Move the early setting of PSCI_RESULT_REG to a later stage
avoiding the early override of the FID that's stored in
the same register.

No functional change.

Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xxxxxxxxxx>
---
 xen/arch/arm/traps.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/xen/arch/arm/traps.c b/xen/arch/arm/traps.c
index 92b1d80..c5a4d41 100644
--- a/xen/arch/arm/traps.c
+++ b/xen/arch/arm/traps.c
@@ -1335,8 +1335,6 @@ static void do_trap_psci(struct cpu_user_regs *regs)
 {
     register_t fid = PSCI_ARG(regs,0);
 
-    /* preloading in case psci_mode_check fails */
-    PSCI_RESULT_REG(regs) = PSCI_INVALID_PARAMETERS;
     switch( fid )
     {
     case PSCI_cpu_off:
@@ -1369,6 +1367,7 @@ static void do_trap_psci(struct cpu_user_regs *regs)
     case PSCI_0_2_FN_MIGRATE_INFO_UP_CPU:
     case PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU:
         perfc_incr(vpsci_migrate_info_up_cpu);
+        PSCI_RESULT_REG(regs) = PSCI_INVALID_PARAMETERS;
         if ( psci_mode_check(current->domain, fid) )
             PSCI_RESULT_REG(regs) = do_psci_0_2_migrate_info_up_cpu();
         break;
@@ -1385,6 +1384,7 @@ static void do_trap_psci(struct cpu_user_regs *regs)
     case PSCI_0_2_FN_CPU_ON:
     case PSCI_0_2_FN64_CPU_ON:
         perfc_incr(vpsci_cpu_on);
+        PSCI_RESULT_REG(regs) = PSCI_INVALID_PARAMETERS;
         if ( psci_mode_check(current->domain, fid) )
         {
             register_t vcpuid = PSCI_ARG(regs,1);
@@ -1397,6 +1397,7 @@ static void do_trap_psci(struct cpu_user_regs *regs)
     case PSCI_0_2_FN_CPU_SUSPEND:
     case PSCI_0_2_FN64_CPU_SUSPEND:
         perfc_incr(vpsci_cpu_suspend);
+        PSCI_RESULT_REG(regs) = PSCI_INVALID_PARAMETERS;
         if ( psci_mode_check(current->domain, fid) )
         {
             uint32_t pstate = PSCI_ARG32(regs,1);
@@ -1409,6 +1410,7 @@ static void do_trap_psci(struct cpu_user_regs *regs)
     case PSCI_0_2_FN_AFFINITY_INFO:
     case PSCI_0_2_FN64_AFFINITY_INFO:
         perfc_incr(vpsci_cpu_affinity_info);
+        PSCI_RESULT_REG(regs) = PSCI_INVALID_PARAMETERS;
         if ( psci_mode_check(current->domain, fid) )
         {
             register_t taff = PSCI_ARG(regs,1);
@@ -1420,6 +1422,7 @@ static void do_trap_psci(struct cpu_user_regs *regs)
     case PSCI_0_2_FN_MIGRATE:
     case PSCI_0_2_FN64_MIGRATE:
         perfc_incr(vpsci_cpu_migrate);
+        PSCI_RESULT_REG(regs) = PSCI_INVALID_PARAMETERS;
         if ( psci_mode_check(current->domain, fid) )
         {
             uint32_t tcpu = PSCI_ARG32(regs,1);
-- 
2.7.4


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