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| author | Zhuojia Shen <chaosdefinition@hotmail.com> | 2023-06-06 10:19:40 +0100 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2023-06-06 10:19:40 +0100 |
| commit | f9ac778898cb28307e0f91421aba34d43c34b679 (patch) | |
| tree | bb19b404245559a155a6269198417c6dd633250b /target/arm/cpu.c | |
| parent | c81e4ab370e858550852b052f689a0a721b879d4 (diff) | |
| download | focaccia-qemu-f9ac778898cb28307e0f91421aba34d43c34b679.tar.gz focaccia-qemu-f9ac778898cb28307e0f91421aba34d43c34b679.zip | |
target/arm: trap DCC access in user mode emulation
Accessing EL0-accessible Debug Communication Channel (DCC) registers in user mode emulation is currently enabled. However, it does not match Linux behavior as Linux sets MDSCR_EL1.TDCC on startup to disable EL0 access to DCC (see __cpu_setup() in arch/arm64/mm/proc.S). This patch fixes access_tdcc() to check MDSCR_EL1.TDCC for EL0 and sets MDSCR_EL1.TDCC for user mode emulation to match Linux. Signed-off-by: Zhuojia Shen <chaosdefinition@hotmail.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-id: DS7PR12MB630905198DD8E69F6817544CAC4EA@DS7PR12MB6309.namprd12.prod.outlook.com Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'target/arm/cpu.c')
| -rw-r--r-- | target/arm/cpu.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/target/arm/cpu.c b/target/arm/cpu.c index 5182ed0c91..4d5bb57f07 100644 --- a/target/arm/cpu.c +++ b/target/arm/cpu.c @@ -289,6 +289,8 @@ static void arm_cpu_reset_hold(Object *obj) * This is not yet exposed from the Linux kernel in any way. */ env->cp15.sctlr_el[1] |= SCTLR_TSCXT; + /* Disable access to Debug Communication Channel (DCC). */ + env->cp15.mdscr_el1 |= 1 << 12; #else /* Reset into the highest available EL */ if (arm_feature(env, ARM_FEATURE_EL3)) { |