From: James Morse <james.morse@xxxxxxx>
[ Upstream commit: 222fc0c8503d98cec3cb2bac2780cdd21a6e31c0 ]
Compat user-space is unable to perform ICIMVAU instructions from
user-space. Instead it uses a compat-syscall. Add the workaround for
Neoverse-N1 #1542419 to this code path.
Signed-off-by: James Morse <james.morse@xxxxxxx>
Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx>
Signed-off-by: James Morse <james.morse@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/arm64/kernel/sys_compat.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/arch/arm64/kernel/sys_compat.c b/arch/arm64/kernel/sys_compat.c
index 010212d35700e..5a9b220aef6cf 100644
--- a/arch/arm64/kernel/sys_compat.c
+++ b/arch/arm64/kernel/sys_compat.c
@@ -19,6 +19,7 @@
*/
#include <linux/compat.h>
+#include <linux/cpufeature.h>
#include <linux/personality.h>
#include <linux/sched.h>
#include <linux/sched/signal.h>
@@ -28,6 +29,7 @@
#include <asm/cacheflush.h>
#include <asm/system_misc.h>
+#include <asm/tlbflush.h>
#include <asm/unistd.h>
static long
@@ -41,6 +43,15 @@ __do_compat_cache_op(unsigned long start, unsigned long end)
if (fatal_signal_pending(current))
return 0;
+ if (cpus_have_const_cap(ARM64_WORKAROUND_1542419)) {
+ /*
+ * The workaround requires an inner-shareable tlbi.
+ * We pick the reserved-ASID to minimise the impact.
+ */
+ __tlbi(aside1is, 0);
+ dsb(ish);
+ }
+
ret = __flush_cache_user_range(start, start + chunk);
if (ret)
return ret;
--
2.20.1
