Factor out the code used for setting the MTE TCF0 field from the prctl code into a convenient function. Other subsystems, like gdbstub, need to set this field as well, so keep it as a separate function to avoid duplication and ensure consistency in how this field is set across the board.
Signed-off-by: Gustavo Romero <gustavo.rom...@linaro.org> --- linux-user/aarch64/mte_user_helper.h | 38 ++++++++++++++++++++++++++++ linux-user/aarch64/target_prctl.h | 22 ++-------------- 2 files changed, 40 insertions(+), 20 deletions(-) create mode 100644 linux-user/aarch64/mte_user_helper.h diff --git a/linux-user/aarch64/mte_user_helper.h b/linux-user/aarch64/mte_user_helper.h new file mode 100644 index 0000000000..fd92e71c00 --- /dev/null +++ b/linux-user/aarch64/mte_user_helper.h @@ -0,0 +1,38 @@ +/* + * ARM MemTag convenience functions. + * + * This code is licensed under the GNU GPL v2 or later. + * + * SPDX-License-Identifier: LGPL-2.1-or-later + */ + +#ifndef MTE_H +#define MTE_H + +#include "sys/prctl.h" + +static inline void arm_set_mte_tcf0(CPUArchState *env, abi_long value) +{ + /* + * Write PR_MTE_TCF to SCTLR_EL1[TCF0]. + * + * The kernel has a per-cpu configuration for the sysadmin, + * /sys/devices/system/cpu/cpu<N>/mte_tcf_preferred, + * which qemu does not implement. + * + * Because there is no performance difference between the modes, and + * because SYNC is most useful for debugging MTE errors, choose SYNC + * as the preferred mode. With this preference, and the way the API + * uses only two bits, there is no way for the program to select + * ASYMM mode. + */ + unsigned tcf = 0; + if (value & PR_MTE_TCF_SYNC) { + tcf = 1; + } else if (value & PR_MTE_TCF_ASYNC) { + tcf = 2; + } + env->cp15.sctlr_el[1] = deposit64(env->cp15.sctlr_el[1], 38, 2, tcf); +} + +#endif /* MTE_H */ diff --git a/linux-user/aarch64/target_prctl.h b/linux-user/aarch64/target_prctl.h index aa8e203c15..ed75b9e4b5 100644 --- a/linux-user/aarch64/target_prctl.h +++ b/linux-user/aarch64/target_prctl.h @@ -7,6 +7,7 @@ #define AARCH64_TARGET_PRCTL_H #include "target/arm/cpu-features.h" +#include "mte_user_helper.h" static abi_long do_prctl_sve_get_vl(CPUArchState *env) { @@ -173,26 +174,7 @@ static abi_long do_prctl_set_tagged_addr_ctrl(CPUArchState *env, abi_long arg2) env->tagged_addr_enable = arg2 & PR_TAGGED_ADDR_ENABLE; if (cpu_isar_feature(aa64_mte, cpu)) { - /* - * Write PR_MTE_TCF to SCTLR_EL1[TCF0]. - * - * The kernel has a per-cpu configuration for the sysadmin, - * /sys/devices/system/cpu/cpu<N>/mte_tcf_preferred, - * which qemu does not implement. - * - * Because there is no performance difference between the modes, and - * because SYNC is most useful for debugging MTE errors, choose SYNC - * as the preferred mode. With this preference, and the way the API - * uses only two bits, there is no way for the program to select - * ASYMM mode. - */ - unsigned tcf = 0; - if (arg2 & PR_MTE_TCF_SYNC) { - tcf = 1; - } else if (arg2 & PR_MTE_TCF_ASYNC) { - tcf = 2; - } - env->cp15.sctlr_el[1] = deposit64(env->cp15.sctlr_el[1], 38, 2, tcf); + arm_set_mte_tcf0(env, arg2); /* * Write PR_MTE_TAG to GCR_EL1[Exclude]. -- 2.34.1