Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/arm64/kernel/syscall.c b/arch/arm64/kernel/syscall.c
index 032d223..871c739 100644
--- a/arch/arm64/kernel/syscall.c
+++ b/arch/arm64/kernel/syscall.c
@@ -8,21 +8,21 @@
#include <linux/syscalls.h>
#include <asm/daifflags.h>
+#include <asm/debug-monitors.h>
#include <asm/fpsimd.h>
#include <asm/syscall.h>
#include <asm/thread_info.h>
#include <asm/unistd.h>
-long compat_arm_syscall(struct pt_regs *regs);
-
+long compat_arm_syscall(struct pt_regs *regs, int scno);
long sys_ni_syscall(void);
-asmlinkage long do_ni_syscall(struct pt_regs *regs)
+static long do_ni_syscall(struct pt_regs *regs, int scno)
{
#ifdef CONFIG_COMPAT
long ret;
if (is_compat_task()) {
- ret = compat_arm_syscall(regs);
+ ret = compat_arm_syscall(regs, scno);
if (ret != -ENOSYS)
return ret;
}
@@ -47,7 +47,7 @@
syscall_fn = syscall_table[array_index_nospec(scno, sc_nr)];
ret = __invoke_syscall(regs, syscall_fn);
} else {
- ret = do_ni_syscall(regs);
+ ret = do_ni_syscall(regs, scno);
}
regs->regs[0] = ret;
@@ -61,6 +61,35 @@
int syscall_trace_enter(struct pt_regs *regs);
void syscall_trace_exit(struct pt_regs *regs);
+#ifdef CONFIG_ARM64_ERRATUM_1463225
+DECLARE_PER_CPU(int, __in_cortex_a76_erratum_1463225_wa);
+
+static void cortex_a76_erratum_1463225_svc_handler(void)
+{
+ u32 reg, val;
+
+ if (!unlikely(test_thread_flag(TIF_SINGLESTEP)))
+ return;
+
+ if (!unlikely(this_cpu_has_cap(ARM64_WORKAROUND_1463225)))
+ return;
+
+ __this_cpu_write(__in_cortex_a76_erratum_1463225_wa, 1);
+ reg = read_sysreg(mdscr_el1);
+ val = reg | DBG_MDSCR_SS | DBG_MDSCR_KDE;
+ write_sysreg(val, mdscr_el1);
+ asm volatile("msr daifclr, #8");
+ isb();
+
+ /* We will have taken a single-step exception by this point */
+
+ write_sysreg(reg, mdscr_el1);
+ __this_cpu_write(__in_cortex_a76_erratum_1463225_wa, 0);
+}
+#else
+static void cortex_a76_erratum_1463225_svc_handler(void) { }
+#endif /* CONFIG_ARM64_ERRATUM_1463225 */
+
static void el0_svc_common(struct pt_regs *regs, int scno, int sc_nr,
const syscall_fn_t syscall_table[])
{
@@ -69,6 +98,7 @@
regs->orig_x0 = regs->regs[0];
regs->syscallno = scno;
+ cortex_a76_erratum_1463225_svc_handler();
local_daif_restore(DAIF_PROCCTX);
user_exit();