The DAIF and PAC checks used raise_exception_ra to raise an exception
and unwind CPU state but raise_exception_ra is currently designed for
handling data aborts as the syndrome is partially precomputed and
encoded in the TB and then merged in merge_syn_data_abort when handling
the data abort. Using raise_exception_ra for DAIF and PAC checks
results in an empty syndrome being retrieved from data[2] in
restore_state_to_opc and setting ESR to 0. This manifested as:
kvm [571]: Unknown exception class: esr: 0x000000 –
Unknown/Uncategorized
when launching a KVM guest when the host qemu used a CPU supporting
EL2+pointer authentication and enabling pointer authentication in the
guest.
As the syndrome and exception class is not encoded in the TB, use
cpu_restore_state and raise_exception to restore the CPU state and raise
the exception with the correct syndrome.
Fixes: 0d43e1a2d29a ("target/arm: Add PAuth helpers")
Cc: Richard Henderson <richard.hender...@linaro.org>
Cc: Peter Maydell <peter.mayd...@linaro.org>
Signed-off-by: Jamie Iles <ja...@nuviainc.com>
---
target/arm/helper-a64.c | 12 +++++++-----
target/arm/pauth_helper.c | 4 +++-
2 files changed, 10 insertions(+), 6 deletions(-)
diff --git a/target/arm/helper-a64.c b/target/arm/helper-a64.c
index 9cc3b066e28b..83991d783fc1 100644
--- a/target/arm/helper-a64.c
+++ b/target/arm/helper-a64.c
@@ -72,11 +72,13 @@ static void daif_check(CPUARMState *env, uint32_t op,
{
/* DAIF update to PSTATE. This is OK from EL0 only if UMA is set. */
if (arm_current_el(env) == 0 && !(arm_sctlr(env, 0) & SCTLR_UMA)) {
- raise_exception_ra(env, EXCP_UDEF,
- syn_aa64_sysregtrap(0, extract32(op, 0, 3),
- extract32(op, 3, 3), 4,
- imm, 0x1f, 0),
- exception_target_el(env), ra);
+ CPUState *cs = env_cpu(env);
+ cpu_restore_state(cs, ra, true);
+ raise_exception(env, EXCP_UDEF,
+ syn_aa64_sysregtrap(0, extract32(op, 0, 3),
+ extract32(op, 3, 3), 4,
+ imm, 0x1f, 0),
+ exception_target_el(env));
}
}
diff --git a/target/arm/pauth_helper.c b/target/arm/pauth_helper.c
index cd6df18150bf..c90a3f765b9c 100644
--- a/target/arm/pauth_helper.c
+++ b/target/arm/pauth_helper.c
@@ -385,7 +385,9 @@ static uint64_t pauth_strip(CPUARMState *env, uint64_t ptr,
bool data)
static void QEMU_NORETURN pauth_trap(CPUARMState *env, int target_el,
uintptr_t ra)
{
- raise_exception_ra(env, EXCP_UDEF, syn_pactrap(), target_el, ra);
+ CPUState *cs = env_cpu(env);
+ cpu_restore_state(cs, ra, true);
+ raise_exception(env, EXCP_UDEF, syn_pactrap(), target_el);
}
static void pauth_check_trap(CPUARMState *env, int el, uintptr_t ra)
--
2.30.2
