[PATCH v8 2/6] arm64: traps: Allow force_signal_inject to pass esr error code

Amit Daniel Kachhap
2020-09-14T08:38:42Z

Some error signal need to pass proper ARM esr error code to userspace to
better identify the cause of the signal. So the function
force_signal_inject is extended to pass this as a parameter. The
existing code is not affected by this change.

Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
---
arch/arm64/include/asm/traps.h | 2 +-
arch/arm64/kernel/fpsimd.c | 4 ++--
arch/arm64/kernel/traps.c | 14 +++++++-------
3 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/arch/arm64/include/asm/traps.h b/arch/arm64/include/asm/traps.h
index cee5928e1b7d..d96dc2c7c09d 100644
--- a/arch/arm64/include/asm/traps.h
+++ b/arch/arm64/include/asm/traps.h
@@ -24,7 +24,7 @@ struct undef_hook {

void register_undef_hook(struct undef_hook *hook);
void unregister_undef_hook(struct undef_hook *hook);
-void force_signal_inject(int signal, int code, unsigned long address);
+void force_signal_inject(int signal, int code, unsigned long address, unsigned int err);
void arm64_notify_segfault(unsigned long addr);
void arm64_force_sig_fault(int signo, int code, void __user *addr, const char *str);
void arm64_force_sig_mceerr(int code, void __user *addr, short lsb, const char *str);
diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c
index 55c8f3ec6705..77484359d44a 100644
--- a/arch/arm64/kernel/fpsimd.c
+++ b/arch/arm64/kernel/fpsimd.c
@@ -312,7 +312,7 @@ static void fpsimd_save(void)
* re-enter user with corrupt state.
* There's no way to recover, so kill it:
*/
- force_signal_inject(SIGKILL, SI_KERNEL, 0);
+ force_signal_inject(SIGKILL, SI_KERNEL, 0, 0);
return;
}

@@ -936,7 +936,7 @@ void do_sve_acc(unsigned int esr, struct pt_regs *regs)
{
/* Even if we chose not to use SVE, the hardware could still trap: */
if (unlikely(!system_supports_sve()) || WARN_ON(is_compat_task())) {
- force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc);
+ force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc, 0);
return;
}

diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index 13ebd5ca2070..29fd00fe94f2 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -412,7 +412,7 @@ static int call_undef_hook(struct pt_regs *regs)
return fn ? fn(regs, instr) : 1;
}

-void force_signal_inject(int signal, int code, unsigned long address)
+void force_signal_inject(int signal, int code, unsigned long address, unsigned int err)
{
const char *desc;
struct pt_regs *regs = current_pt_regs();
@@ -438,7 +438,7 @@ void force_signal_inject(int signal, int code, unsigned long address)
signal = SIGKILL;
}

- arm64_notify_die(desc, regs, signal, code, (void __user *)address, 0);
+ arm64_notify_die(desc, regs, signal, code, (void __user *)address, err);
}

/*
@@ -455,7 +455,7 @@ void arm64_notify_segfault(unsigned long addr)
code = SEGV_ACCERR;
mmap_read_unlock(current->mm);

- force_signal_inject(SIGSEGV, code, addr);
+ force_signal_inject(SIGSEGV, code, addr, 0);
}

void do_undefinstr(struct pt_regs *regs)
@@ -468,14 +468,14 @@ void do_undefinstr(struct pt_regs *regs)
return;

BUG_ON(!user_mode(regs));
- force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc);
+ force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc, 0);
}
NOKPROBE_SYMBOL(do_undefinstr);

void do_bti(struct pt_regs *regs)
{
BUG_ON(!user_mode(regs));
- force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc);
+ force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc, 0);
}
NOKPROBE_SYMBOL(do_bti);

@@ -528,7 +528,7 @@ static void user_cache_maint_handler(unsigned int esr, struct pt_regs *regs)
__user_cache_maint("ic ivau", address, ret);
break;
default:
- force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc);
+ force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc, 0);
return;
}

@@ -581,7 +581,7 @@ static void mrs_handler(unsigned int esr, struct pt_regs *regs)
sysreg = esr_sys64_to_sysreg(esr);

if (do_emulate_mrs(regs, sysreg, rt) != 0)
- force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc);
+ force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc, 0);
}

static void wfi_handler(unsigned int esr, struct pt_regs *regs)