From 39e54499280f373d03ab7ffe681ca9d53a9089c9 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Tue, 27 Dec 2022 14:20:41 +0000 Subject: [PATCH] arm64/signal: Include TPIDR2 in the signal context Add a new signal frame record for TPIDR2 using the same format as we already use for ESR with different magic, a header with the value from the register appended as the only data. If SME is supported then this record is always included. Signed-off-by: Mark Brown Reviewed-by: Szabolcs Nagy Link: https://lore.kernel.org/r/20221208-arm64-tpidr2-sig-v3-2-c77c6c8775f4@kernel.org Signed-off-by: Catalin Marinas --- arch/arm64/include/uapi/asm/sigcontext.h | 8 +++++ arch/arm64/kernel/signal.c | 59 ++++++++++++++++++++++++++++++++ 2 files changed, 67 insertions(+) diff --git a/arch/arm64/include/uapi/asm/sigcontext.h b/arch/arm64/include/uapi/asm/sigcontext.h index 9525041..4b4398d 100644 --- a/arch/arm64/include/uapi/asm/sigcontext.h +++ b/arch/arm64/include/uapi/asm/sigcontext.h @@ -144,6 +144,14 @@ struct sve_context { #define SVE_SIG_FLAG_SM 0x1 /* Context describes streaming mode */ +/* TPIDR2_EL0 context */ +#define TPIDR2_MAGIC 0x54504902 + +struct tpidr2_context { + struct _aarch64_ctx head; + __u64 tpidr2; +}; + #define ZA_MAGIC 0x54366345 struct za_context { diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c index e0d09bf..5fe45c7 100644 --- a/arch/arm64/kernel/signal.c +++ b/arch/arm64/kernel/signal.c @@ -56,6 +56,7 @@ struct rt_sigframe_user_layout { unsigned long fpsimd_offset; unsigned long esr_offset; unsigned long sve_offset; + unsigned long tpidr2_offset; unsigned long za_offset; unsigned long extra_offset; unsigned long end_offset; @@ -220,6 +221,7 @@ static int restore_fpsimd_context(struct fpsimd_context __user *ctx) struct user_ctxs { struct fpsimd_context __user *fpsimd; struct sve_context __user *sve; + struct tpidr2_context __user *tpidr2; struct za_context __user *za; }; @@ -361,6 +363,32 @@ extern int preserve_sve_context(void __user *ctx); #ifdef CONFIG_ARM64_SME +static int preserve_tpidr2_context(struct tpidr2_context __user *ctx) +{ + int err = 0; + + current->thread.tpidr2_el0 = read_sysreg_s(SYS_TPIDR2_EL0); + + __put_user_error(TPIDR2_MAGIC, &ctx->head.magic, err); + __put_user_error(sizeof(*ctx), &ctx->head.size, err); + __put_user_error(current->thread.tpidr2_el0, &ctx->tpidr2, err); + + return err; +} + +static int restore_tpidr2_context(struct user_ctxs *user) +{ + u64 tpidr2_el0; + int err = 0; + + /* Magic and size were validated deciding to call this function */ + __get_user_error(tpidr2_el0, &user->tpidr2->tpidr2, err); + if (!err) + current->thread.tpidr2_el0 = tpidr2_el0; + + return err; +} + static int preserve_za_context(struct za_context __user *ctx) { int err = 0; @@ -450,6 +478,8 @@ static int restore_za_context(struct user_ctxs *user) #else /* ! CONFIG_ARM64_SME */ /* Turn any non-optimised out attempts to use these into a link error: */ +extern int preserve_tpidr2_context(void __user *ctx); +extern int restore_tpidr2_context(struct user_ctxs *user); extern int preserve_za_context(void __user *ctx); extern int restore_za_context(struct user_ctxs *user); @@ -468,6 +498,7 @@ static int parse_user_sigframe(struct user_ctxs *user, user->fpsimd = NULL; user->sve = NULL; + user->tpidr2 = NULL; user->za = NULL; if (!IS_ALIGNED((unsigned long)base, 16)) @@ -534,6 +565,19 @@ static int parse_user_sigframe(struct user_ctxs *user, user->sve = (struct sve_context __user *)head; break; + case TPIDR2_MAGIC: + if (!system_supports_sme()) + goto invalid; + + if (user->tpidr2) + goto invalid; + + if (size != sizeof(*user->tpidr2)) + goto invalid; + + user->tpidr2 = (struct tpidr2_context __user *)head; + break; + case ZA_MAGIC: if (!system_supports_sme()) goto invalid; @@ -666,6 +710,9 @@ static int restore_sigframe(struct pt_regs *regs, err = restore_fpsimd_context(user.fpsimd); } + if (err == 0 && system_supports_sme() && user.tpidr2) + err = restore_tpidr2_context(&user); + if (err == 0 && system_supports_sme() && user.za) err = restore_za_context(&user); @@ -760,6 +807,11 @@ static int setup_sigframe_layout(struct rt_sigframe_user_layout *user, else vl = task_get_sme_vl(current); + err = sigframe_alloc(user, &user->tpidr2_offset, + sizeof(struct tpidr2_context)); + if (err) + return err; + if (thread_za_enabled(¤t->thread)) vq = sve_vq_from_vl(vl); @@ -817,6 +869,13 @@ static int setup_sigframe(struct rt_sigframe_user_layout *user, err |= preserve_sve_context(sve_ctx); } + /* TPIDR2 if supported */ + if (system_supports_sme() && err == 0) { + struct tpidr2_context __user *tpidr2_ctx = + apply_user_offset(user, user->tpidr2_offset); + err |= preserve_tpidr2_context(tpidr2_ctx); + } + /* ZA state if present */ if (system_supports_sme() && err == 0 && user->za_offset) { struct za_context __user *za_ctx = -- 2.7.4