x86/hyperv: Fix hv_get/set_register for nested bringup

hv_get_nested_reg only translates SINT0, resulting in the wrong sint
being registered by nested vmbus.

Fix the issue with new utility function hv_is_sint_reg.

While at it, improve clarity of hv_set_non_nested_register and hv_is_synic_reg.

Signed-off-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
Reviewed-by: Jinank Jain <jinankjain@linux.microsoft.com>
Link: https://lore.kernel.org/r/1675980172-6851-1-git-send-email-nunodasneves@linux.microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>

diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
index 15ac2d03ac59bdc074b8a17f231ab61e5177c6fc..4c4c0ec3b62e81dc2908bb2b115f98bf94bb7c00 100644 (file)
--- a/arch/x86/include/asm/mshyperv.h
+++ b/arch/x86/include/asm/mshyperv.h
@@ -224,10 +224,14 @@ extern bool hv_isolation_type_snp(void);
 
 static inline bool hv_is_synic_reg(unsigned int reg)
 {
-       if ((reg >= HV_REGISTER_SCONTROL) &&
-           (reg <= HV_REGISTER_SINT15))
-               return true;
-       return false;
+       return (reg >= HV_REGISTER_SCONTROL) &&
+              (reg <= HV_REGISTER_SINT15);
+}
+
+static inline bool hv_is_sint_reg(unsigned int reg)
+{
+       return (reg >= HV_REGISTER_SINT0) &&
+              (reg <= HV_REGISTER_SINT15);
 }
 
 u64 hv_get_register(unsigned int reg);

diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index dedec2f23ad103a37f34ab9106372604a1aab76b..f924a76c6923d01371679247b13615197fe61b42 100644 (file)
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -44,6 +44,9 @@ struct ms_hyperv_info ms_hyperv;
 #if IS_ENABLED(CONFIG_HYPERV)
 static inline unsigned int hv_get_nested_reg(unsigned int reg)
 {
+       if (hv_is_sint_reg(reg))
+               return reg - HV_REGISTER_SINT0 + HV_REGISTER_NESTED_SINT0;
+
        switch (reg) {
        case HV_REGISTER_SIMP:
                return HV_REGISTER_NESTED_SIMP;
@@ -53,8 +56,6 @@ static inline unsigned int hv_get_nested_reg(unsigned int reg)
                return HV_REGISTER_NESTED_SVERSION;
        case HV_REGISTER_SCONTROL:
                return HV_REGISTER_NESTED_SCONTROL;
-       case HV_REGISTER_SINT0:
-               return HV_REGISTER_NESTED_SINT0;
        case HV_REGISTER_EOM:
                return HV_REGISTER_NESTED_EOM;
        default:
@@ -80,8 +81,7 @@ void hv_set_non_nested_register(unsigned int reg, u64 value)
                hv_ghcb_msr_write(reg, value);
 
                /* Write proxy bit via wrmsl instruction */
-               if (reg >= HV_REGISTER_SINT0 &&
-                   reg <= HV_REGISTER_SINT15)
+               if (hv_is_sint_reg(reg))
                        wrmsrl(reg, value | 1 << 20);
        } else {
                wrmsrl(reg, value);