[ 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@arm.com Signed-off-by: Catalin Marinas catalin.marinas@arm.com Signed-off-by: James Morse james.morse@arm.com --- 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 f1cb64959427..c9fb02927d3e 100644 --- a/arch/arm64/kernel/sys_compat.c +++ b/arch/arm64/kernel/sys_compat.c @@ -8,6 +8,7 @@ */
#include <linux/compat.h> +#include <linux/cpufeature.h> #include <linux/personality.h> #include <linux/sched.h> #include <linux/sched/signal.h> @@ -17,6 +18,7 @@
#include <asm/cacheflush.h> #include <asm/system_misc.h> +#include <asm/tlbflush.h> #include <asm/unistd.h>
static long @@ -30,6 +32,15 @@ __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;