The privileged message send and clear instructions (msgsndp & msgclrp)
are privileged, but will generate a hypervisor facility unavailable
exception if not enabled in the HFSCR and executed in privileged
non-hypervisor state.
Add checks when accessing the DPDES register and when using the
msgsndp and msgclrp isntructions.
Based on previous work from Suraj Jitindar Singh.
Cc: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
---
target/ppc/cpu.h | 6 ++++++
target/ppc/excp_helper.c | 13 +++++++++++++
target/ppc/misc_helper.c | 27 +++++++++++++++++++++++++++
3 files changed, 46 insertions(+)
diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h
index d175ec9a641d..1ff6afbccdb2 100644
--- a/target/ppc/cpu.h
+++ b/target/ppc/cpu.h
@@ -397,6 +397,10 @@ typedef struct ppc_v3_pate_t {
#define PSSCR_ESL PPC_BIT(42) /* Enable State Loss */
#define PSSCR_EC PPC_BIT(43) /* Exit Criterion */
+/* HFSCR bits */
+#define HFSCR_MSGP PPC_BIT(53) /* Privileged Message Send Facilities */
+#define HFSCR_IC_MSGP 0xA
+
#define msr_sf ((env->msr >> MSR_SF) & 1)
#define msr_isf ((env->msr >> MSR_ISF) & 1)
#define msr_shv ((env->msr >> MSR_SHV) & 1)
@@ -1332,6 +1336,8 @@ void cpu_ppc_set_vhyp(PowerPCCPU *cpu, PPCVirtualHypervisor *vhyp);
#endif
void store_fpscr(CPUPPCState *env, uint64_t arg, uint32_t mask);
+void helper_hfscr_facility_check(CPUPPCState *env, uint32_t bit,
+ const char *caller, uint32_t cause);
static inline uint64_t ppc_dump_gpr(CPUPPCState *env, int gprn)
{
diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c
index 343f3a6b30c4..3887f8888c6c 100644
--- a/target/ppc/excp_helper.c
+++ b/target/ppc/excp_helper.c
@@ -471,6 +471,15 @@ static inline void powerpc_excp(PowerPCCPU *cpu, int excp_model, int excp)
case POWERPC_EXCP_FU: /* Facility unavailable exception */
#ifdef TARGET_PPC64
env->spr[SPR_FSCR] |= ((target_ulong)env->error_code << 56);
+#endif
+ break;
+ case POWERPC_EXCP_HV_FU: /* Hypervisor Facility Unavailable Exception */
+#ifdef TARGET_PPC64
+ env->spr[SPR_HFSCR] |= ((target_ulong)env->error_code << FSCR_IC_POS);
+ srr0 = SPR_HSRR0;
+ srr1 = SPR_HSRR1;
+ new_msr |= (target_ulong)MSR_HVB;
+ new_msr |= env->msr & ((target_ulong)1 << MSR_RI);
#endif
break;
case POWERPC_EXCP_PIT: /* Programmable interval timer interrupt */
@@ -1287,6 +1296,8 @@ void helper_book3s_msgclrp(CPUPPCState *env, target_ulong rb)
{
int irq = book3s_dbell2irq(rb, false);
+ helper_hfscr_facility_check(env, HFSCR_MSGP, "msgclrp", HFSCR_IC_MSGP);
+
if (irq < 0) {
return;
}
@@ -1303,6 +1314,8 @@ void helper_book3s_msgsndp(CPUPPCState *env, target_ulong rb)
int irq = book3s_dbell2irq(rb, false);
int pir = env->spr_cb[SPR_PIR].default_value;
+ helper_hfscr_facility_check(env, HFSCR_MSGP, "msgsndp", HFSCR_IC_MSGP);
+
if (irq < 0) {
return;
}
diff --git a/target/ppc/misc_helper.c b/target/ppc/misc_helper.c
index 66b5b0824208..2ff6bed10228 100644
--- a/target/ppc/misc_helper.c
+++ b/target/ppc/misc_helper.c
@@ -41,6 +41,18 @@ void helper_store_dump_spr(CPUPPCState *env, uint32_t sprn)
}
#ifdef TARGET_PPC64
+static void raise_hv_fu_exception(CPUPPCState *env, uint32_t bit,
+ const char *caller, uint32_t cause,
+ uintptr_t raddr)
+{
+ qemu_log_mask(LOG_GUEST_ERROR, "HV Facility %d is unavailable (%s)\n",
+ bit, caller);
+
+ env->spr[SPR_HFSCR] &= ~((target_ulong)FSCR_IC_MASK << FSCR_IC_POS);
+
+ raise_exception_err_ra(env, POWERPC_EXCP_HV_FU, cause, raddr);
+}
+
static void raise_fu_exception(CPUPPCState *env, uint32_t bit,
uint32_t sprn, uint32_t cause,
uintptr_t raddr)
@@ -55,6 +67,17 @@ static void raise_fu_exception(CPUPPCState *env, uint32_t bit,
}
#endif
+void helper_hfscr_facility_check(CPUPPCState *env, uint32_t bit,
+ const char *caller, uint32_t cause)
+{
+#ifdef TARGET_PPC64
+ if ((env->msr_mask & MSR_HVB) && !msr_hv &&
+ !(env->spr[SPR_HFSCR] & (1UL << bit))) {
+ raise_hv_fu_exception(env, bit, caller, cause, GETPC());
+ }
+#endif
+}
+
void helper_fscr_facility_check(CPUPPCState *env, uint32_t bit,
uint32_t sprn, uint32_t cause)
{
@@ -114,6 +137,8 @@ target_ulong helper_load_dpdes(CPUPPCState *env)
{
target_ulong dpdes = 0;
+ helper_hfscr_facility_check(env, HFSCR_MSGP, "load DPDES", HFSCR_IC_MSGP);
+
/* TODO: TCG supports only one thread */
if (env->pending_interrupts & (1 << PPC_INTERRUPT_DOORBELL)) {
dpdes |= (env->spr_cb[SPR_PIR].default_value & DBELL_TIRTAG_MASK);
@@ -127,6 +152,8 @@ void helper_store_dpdes(CPUPPCState *env, target_ulong val)
PowerPCCPU *cpu = env_archcpu(env);
CPUState *cs = CPU(cpu);
+ helper_hfscr_facility_check(env, HFSCR_MSGP, "store DPDES", HFSCR_IC_MSGP);
+
/* TODO: TCG supports only one thread */
if (val & ~0x1) {
qemu_log_mask(LOG_GUEST_ERROR, "Invalid DPDES register value "
--
2.21.1
On Thu, Jan 09, 2020 at 05:33:46PM +0100, Cédric Le Goater wrote:
> The privileged message send and clear instructions (msgsndp & msgclrp)
> are privileged, but will generate a hypervisor facility unavailable
> exception if not enabled in the HFSCR and executed in privileged
> non-hypervisor state.
>
> Add checks when accessing the DPDES register and when using the
> msgsndp and msgclrp isntructions.
>
> Based on previous work from Suraj Jitindar Singh.
>
> Cc: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
> Signed-off-by: Cédric Le Goater <clg@kaod.org>
> ---
> target/ppc/cpu.h | 6 ++++++
> target/ppc/excp_helper.c | 13 +++++++++++++
> target/ppc/misc_helper.c | 27 +++++++++++++++++++++++++++
> 3 files changed, 46 insertions(+)
>
> diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h
> index d175ec9a641d..1ff6afbccdb2 100644
> --- a/target/ppc/cpu.h
> +++ b/target/ppc/cpu.h
> @@ -397,6 +397,10 @@ typedef struct ppc_v3_pate_t {
> #define PSSCR_ESL PPC_BIT(42) /* Enable State Loss */
> #define PSSCR_EC PPC_BIT(43) /* Exit Criterion */
>
> +/* HFSCR bits */
> +#define HFSCR_MSGP PPC_BIT(53) /* Privileged Message Send Facilities */
> +#define HFSCR_IC_MSGP 0xA
> +
> #define msr_sf ((env->msr >> MSR_SF) & 1)
> #define msr_isf ((env->msr >> MSR_ISF) & 1)
> #define msr_shv ((env->msr >> MSR_SHV) & 1)
> @@ -1332,6 +1336,8 @@ void cpu_ppc_set_vhyp(PowerPCCPU *cpu, PPCVirtualHypervisor *vhyp);
> #endif
>
> void store_fpscr(CPUPPCState *env, uint64_t arg, uint32_t mask);
> +void helper_hfscr_facility_check(CPUPPCState *env, uint32_t bit,
> + const char *caller, uint32_t cause);
>
> static inline uint64_t ppc_dump_gpr(CPUPPCState *env, int gprn)
> {
> diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c
> index 343f3a6b30c4..3887f8888c6c 100644
> --- a/target/ppc/excp_helper.c
> +++ b/target/ppc/excp_helper.c
> @@ -471,6 +471,15 @@ static inline void powerpc_excp(PowerPCCPU *cpu, int excp_model, int excp)
> case POWERPC_EXCP_FU: /* Facility unavailable exception */
> #ifdef TARGET_PPC64
> env->spr[SPR_FSCR] |= ((target_ulong)env->error_code << 56);
> +#endif
> + break;
> + case POWERPC_EXCP_HV_FU: /* Hypervisor Facility Unavailable Exception */
> +#ifdef TARGET_PPC64
> + env->spr[SPR_HFSCR] |= ((target_ulong)env->error_code << FSCR_IC_POS);
> + srr0 = SPR_HSRR0;
> + srr1 = SPR_HSRR1;
> + new_msr |= (target_ulong)MSR_HVB;
> + new_msr |= env->msr & ((target_ulong)1 << MSR_RI);
> #endif
> break;
> case POWERPC_EXCP_PIT: /* Programmable interval timer interrupt */
> @@ -1287,6 +1296,8 @@ void helper_book3s_msgclrp(CPUPPCState *env, target_ulong rb)
> {
> int irq = book3s_dbell2irq(rb, false);
>
> + helper_hfscr_facility_check(env, HFSCR_MSGP, "msgclrp", HFSCR_IC_MSGP);
> +
> if (irq < 0) {
> return;
> }
> @@ -1303,6 +1314,8 @@ void helper_book3s_msgsndp(CPUPPCState *env, target_ulong rb)
> int irq = book3s_dbell2irq(rb, false);
> int pir = env->spr_cb[SPR_PIR].default_value;
>
> + helper_hfscr_facility_check(env, HFSCR_MSGP, "msgsndp", HFSCR_IC_MSGP);
> +
> if (irq < 0) {
> return;
> }
> diff --git a/target/ppc/misc_helper.c b/target/ppc/misc_helper.c
> index 66b5b0824208..2ff6bed10228 100644
> --- a/target/ppc/misc_helper.c
> +++ b/target/ppc/misc_helper.c
> @@ -41,6 +41,18 @@ void helper_store_dump_spr(CPUPPCState *env, uint32_t sprn)
> }
>
> #ifdef TARGET_PPC64
> +static void raise_hv_fu_exception(CPUPPCState *env, uint32_t bit,
> + const char *caller, uint32_t cause,
> + uintptr_t raddr)
> +{
> + qemu_log_mask(LOG_GUEST_ERROR, "HV Facility %d is unavailable (%s)\n",
> + bit, caller);
If we're using pnv and the emulated hypervisor is using HFSCR for
trap-and-emulate or lazy loading or something, then an HV_FU trap
doesn't necessarily indicate an error in the guest, so I'm not sure
that's the right log mask. Maybe just a trace event here?
> + env->spr[SPR_HFSCR] &= ~((target_ulong)FSCR_IC_MASK << FSCR_IC_POS);
> +
> + raise_exception_err_ra(env, POWERPC_EXCP_HV_FU, cause, raddr);
> +}
> +
> static void raise_fu_exception(CPUPPCState *env, uint32_t bit,
> uint32_t sprn, uint32_t cause,
> uintptr_t raddr)
> @@ -55,6 +67,17 @@ static void raise_fu_exception(CPUPPCState *env, uint32_t bit,
> }
> #endif
>
> +void helper_hfscr_facility_check(CPUPPCState *env, uint32_t bit,
> + const char *caller, uint32_t cause)
> +{
> +#ifdef TARGET_PPC64
> + if ((env->msr_mask & MSR_HVB) && !msr_hv &&
> + !(env->spr[SPR_HFSCR] & (1UL << bit))) {
> + raise_hv_fu_exception(env, bit, caller, cause, GETPC());
> + }
> +#endif
> +}
> +
> void helper_fscr_facility_check(CPUPPCState *env, uint32_t bit,
> uint32_t sprn, uint32_t cause)
> {
> @@ -114,6 +137,8 @@ target_ulong helper_load_dpdes(CPUPPCState *env)
> {
> target_ulong dpdes = 0;
>
> + helper_hfscr_facility_check(env, HFSCR_MSGP, "load DPDES", HFSCR_IC_MSGP);
> +
> /* TODO: TCG supports only one thread */
> if (env->pending_interrupts & (1 << PPC_INTERRUPT_DOORBELL)) {
> dpdes |= (env->spr_cb[SPR_PIR].default_value & DBELL_TIRTAG_MASK);
> @@ -127,6 +152,8 @@ void helper_store_dpdes(CPUPPCState *env, target_ulong val)
> PowerPCCPU *cpu = env_archcpu(env);
> CPUState *cs = CPU(cpu);
>
> + helper_hfscr_facility_check(env, HFSCR_MSGP, "store DPDES", HFSCR_IC_MSGP);
> +
> /* TODO: TCG supports only one thread */
> if (val & ~0x1) {
> qemu_log_mask(LOG_GUEST_ERROR, "Invalid DPDES register value "
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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