@@ -98,6 +98,13 @@ struct esr_context {
__u64 esr;
};
+#define POE_MAGIC 0x504f4530
+
+struct poe_context {
+ struct _aarch64_ctx head;
+ __u64 por_el0;
+};
+
/*
* extra_context: describes extra space in the signal frame for
* additional structures that don't fit in sigcontext.__reserved[].
@@ -62,6 +62,7 @@ struct rt_sigframe_user_layout {
unsigned long zt_offset;
unsigned long extra_offset;
unsigned long end_offset;
+ unsigned long poe_offset;
};
#define BASE_SIGFRAME_SIZE round_up(sizeof(struct rt_sigframe), 16)
@@ -182,6 +183,8 @@ struct user_ctxs {
u32 za_size;
struct zt_context __user *zt;
u32 zt_size;
+ struct poe_context __user *poe;
+ u32 poe_size;
};
static int preserve_fpsimd_context(struct fpsimd_context __user *ctx)
@@ -227,6 +230,20 @@ static int restore_fpsimd_context(struct user_ctxs *user)
return err ? -EFAULT : 0;
}
+static int restore_poe_context(struct user_ctxs *user)
+{
+ u64 por_el0;
+ int err = 0;
+
+ if (user->poe_size != sizeof(*user->poe))
+ return -EINVAL;
+
+ __get_user_error(por_el0, &(user->poe->por_el0), err);
+ if (!err)
+ write_sysreg_s(por_el0, SYS_POR_EL0);
+
+ return err;
+}
#ifdef CONFIG_ARM64_SVE
@@ -590,6 +607,7 @@ static int parse_user_sigframe(struct user_ctxs *user,
user->tpidr2 = NULL;
user->za = NULL;
user->zt = NULL;
+ user->poe = NULL;
if (!IS_ALIGNED((unsigned long)base, 16))
goto invalid;
@@ -640,6 +658,17 @@ static int parse_user_sigframe(struct user_ctxs *user,
/* ignore */
break;
+ case POE_MAGIC:
+ if (!system_supports_poe())
+ goto invalid;
+
+ if (user->poe)
+ goto invalid;
+
+ user->poe = (struct poe_context __user *)head;
+ user->poe_size = size;
+ break;
+
case SVE_MAGIC:
if (!system_supports_sve() && !system_supports_sme())
goto invalid;
@@ -812,6 +841,9 @@ static int restore_sigframe(struct pt_regs *regs,
if (err == 0 && system_supports_sme2() && user.zt)
err = restore_zt_context(&user);
+ if (err == 0 && system_supports_poe() && user.poe)
+ err = restore_poe_context(&user);
+
return err;
}
@@ -928,6 +960,13 @@ static int setup_sigframe_layout(struct rt_sigframe_user_layout *user,
}
}
+ if (system_supports_poe()) {
+ err = sigframe_alloc(user, &user->poe_offset,
+ sizeof(struct poe_context));
+ if (err)
+ return err;
+ }
+
return sigframe_alloc_end(user);
}
@@ -968,6 +1007,15 @@ static int setup_sigframe(struct rt_sigframe_user_layout *user,
__put_user_error(current->thread.fault_code, &esr_ctx->esr, err);
}
+ if (system_supports_poe() && err == 0 && user->poe_offset) {
+ struct poe_context __user *poe_ctx =
+ apply_user_offset(user, user->poe_offset);
+
+ __put_user_error(POE_MAGIC, &poe_ctx->head.magic, err);
+ __put_user_error(sizeof(*poe_ctx), &poe_ctx->head.size, err);
+ __put_user_error(read_sysreg_s(SYS_POR_EL0), &poe_ctx->por_el0, err);
+ }
+
/* Scalable Vector Extension state (including streaming), if present */
if ((system_supports_sve() || system_supports_sme()) &&
err == 0 && user->sve_offset) {
@@ -1119,6 +1167,9 @@ static void setup_return(struct pt_regs *regs, struct k_sigaction *ka,
sme_smstop();
}
+ if (system_supports_poe())
+ write_sysreg_s(POR_EL0_INIT, SYS_POR_EL0);
+
if (ka->sa.sa_flags & SA_RESTORER)
sigtramp = ka->sa.sa_restorer;
else
Add PKEY support to signals, by saving and restoring POR_EL0 from the stackframe. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> --- arch/arm64/include/uapi/asm/sigcontext.h | 7 ++++ arch/arm64/kernel/signal.c | 51 ++++++++++++++++++++++++ 2 files changed, 58 insertions(+)