From 5d8f81ba1da55210123b9595e87b913c79579d02 Mon Sep 17 00:00:00 2001 From: Patrick Stählin Date: Fri, 9 Nov 2018 22:42:16 +0100 Subject: RISC-V: recognize S/U mode bits in print_isa MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Removes the warning about an unsupported ISA when reading /proc/cpuinfo on QEMU. The "S" extension is not being returned as it is not accessible from userspace. Signed-off-by: Patrick Stählin Signed-off-by: Palmer Dabbelt --- arch/riscv/kernel/cpu.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'arch') diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c index 3a5a2ee31547..b4a7d4427fbb 100644 --- a/arch/riscv/kernel/cpu.c +++ b/arch/riscv/kernel/cpu.c @@ -64,7 +64,7 @@ int riscv_of_processor_hartid(struct device_node *node) static void print_isa(struct seq_file *f, const char *orig_isa) { - static const char *ext = "mafdc"; + static const char *ext = "mafdcsu"; const char *isa = orig_isa; const char *e; @@ -88,11 +88,14 @@ static void print_isa(struct seq_file *f, const char *orig_isa) /* * Check the rest of the ISA string for valid extensions, printing those * we find. RISC-V ISA strings define an order, so we only print the - * extension bits when they're in order. + * extension bits when they're in order. Hide the supervisor (S) + * extension from userspace as it's not accessible from there. */ for (e = ext; *e != '\0'; ++e) { if (isa[0] == e[0]) { - seq_write(f, isa, 1); + if (isa[0] != 's') + seq_write(f, isa, 1); + isa++; } } -- cgit v1.2.3-59-g8ed1b