signal/arm64: Add and use arm64_force_sig_mceerr as appropriate

Add arm64_force_sig_mceerr for consistency with arm64_force_sig_fault,
and use it in the one location that can take advantage of it.

This removes the fiddly filling out of siginfo before sending a signal
reporting an memory error to userspace.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

3 files changed, 10 insertions, 7 deletions

diff --git a/arch/arm64/include/asm/traps.h b/arch/arm64/include/asm/traps.h
index 08e99901edbc..193f0b0e8ee3 100644
--- a/arch/arm64/include/asm/traps.h
+++ b/arch/arm64/include/asm/traps.h
@@ -38,6 +38,7 @@ void unregister_undef_hook(struct undef_hook *hook);
 void force_signal_inject(int signal, int code, unsigned long address);
 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);
 void arm64_force_sig_info(struct siginfo *info, const char *str);
 
 /*
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index 37a3309863e0..baa96dfffeec 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -255,6 +255,13 @@ void arm64_force_sig_fault(int signo, int code, void __user *addr,
         force_sig_fault(signo, code, addr, current);
 }
 
+void arm64_force_sig_mceerr(int code, void __user *addr, short lsb,
+                            const char *str)
+{
+        arm64_show_signal(SIGBUS, str);
+        force_sig_mceerr(code, addr, lsb, current);
+}
+
 void arm64_force_sig_info(struct siginfo *info, const char *str)
 {
         arm64_show_signal(info->si_signo, str);
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 66c295019a9a..f0ccb209d181 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -422,7 +422,6 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
         const struct fault_info *inf;
         struct task_struct *tsk;
         struct mm_struct *mm;
-        struct siginfo si;
         vm_fault_t fault, major = 0;
         unsigned long vm_flags = VM_READ | VM_WRITE;
         unsigned int mm_flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
@@ -574,12 +573,8 @@ retry:
                 if (fault & VM_FAULT_HWPOISON_LARGE)
                         lsb = hstate_index_to_shift(VM_FAULT_GET_HINDEX(fault));
 
-                clear_siginfo(&si);
-                si.si_signo     = SIGBUS;
-                si.si_code      = BUS_MCEERR_AR;
-                si.si_addr = (void __user *)addr;
-                si.si_addr_lsb  = lsb;
-                arm64_force_sig_info(&si, inf->name);
+                arm64_force_sig_mceerr(BUS_MCEERR_AR, (void __user *)addr, lsb,
+                                       inf->name);
         } else {
                 /*
                  * Something tried to access memory that isn't in our memory