diff options
| author | Peter Maydell <peter.maydell@linaro.org> | 2023-04-24 16:39:08 +0100 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2023-05-02 15:47:41 +0100 |
| commit | 7f3a3d3dc433dc06c0adb480729af80f9c8e3739 (patch) | |
| tree | 1c5b00076207196c8ee7d949a9522ebd91ea7111 /target/arm | |
| parent | 2c5fa0778c3b4307f9f3af7f27886c46d129c62f (diff) | |
target/arm: Define and use new load_cpu_field_low32()
In several places in the 32-bit Arm translate.c, we try to use
load_cpu_field() to load from a CPUARMState field into a TCGv_i32
where the field is actually 64-bit. This works on little-endian
hosts, but gives the wrong half of the register on big-endian.
Add a new load_cpu_field_low32() which loads the low 32 bits
of a 64-bit field into a TCGv_i32. The new macro includes a
compile-time check against accidentally using it on a field
of the wrong size. Use it to fix the two places in the code
where we were using load_cpu_field() on a 64-bit field.
This fixes a bug where on big-endian hosts the guest would
crash after executing an ERET instruction, and a more corner
case one where some UNDEFs for attempted accesses to MSR
banked registers from Secure EL1 might go to the wrong EL.
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230424153909.1419369-2-peter.maydell@linaro.org
Diffstat (limited to 'target/arm')
| -rw-r--r-- | target/arm/tcg/translate.c | 4 | ||||
| -rw-r--r-- | target/arm/translate-a32.h | 7 |
2 files changed, 9 insertions, 2 deletions
diff --git a/target/arm/tcg/translate.c b/target/arm/tcg/translate.c index 3c8401e908..7468476724 100644 --- a/target/arm/tcg/translate.c +++ b/target/arm/tcg/translate.c @@ -2816,7 +2816,7 @@ static bool msr_banked_access_decode(DisasContext *s, int r, int sysm, int rn, if (arm_dc_feature(s, ARM_FEATURE_AARCH64) && dc_isar_feature(aa64_sel2, s)) { /* Target EL is EL<3 minus SCR_EL3.EEL2> */ - tcg_el = load_cpu_field(cp15.scr_el3); + tcg_el = load_cpu_field_low32(cp15.scr_el3); tcg_gen_sextract_i32(tcg_el, tcg_el, ctz32(SCR_EEL2), 1); tcg_gen_addi_i32(tcg_el, tcg_el, 3); } else { @@ -6396,7 +6396,7 @@ static bool trans_ERET(DisasContext *s, arg_ERET *a) } if (s->current_el == 2) { /* ERET from Hyp uses ELR_Hyp, not LR */ - tmp = load_cpu_field(elr_el[2]); + tmp = load_cpu_field_low32(elr_el[2]); } else { tmp = load_reg(s, 14); } diff --git a/target/arm/translate-a32.h b/target/arm/translate-a32.h index 5339c22f1e..99eea85fa8 100644 --- a/target/arm/translate-a32.h +++ b/target/arm/translate-a32.h @@ -61,6 +61,13 @@ static inline TCGv_i32 load_cpu_offset(int offset) #define load_cpu_field(name) load_cpu_offset(offsetof(CPUARMState, name)) +/* Load from the low half of a 64-bit field to a TCGv_i32 */ +#define load_cpu_field_low32(name) \ + ({ \ + QEMU_BUILD_BUG_ON(sizeof_field(CPUARMState, name) != 8); \ + load_cpu_offset(offsetoflow32(CPUARMState, name)); \ + }) + void store_cpu_offset(TCGv_i32 var, int offset, int size); #define store_cpu_field(var, name) \ |