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authorSamuel Holland <samuel.holland@sifive.com>2024-10-16 13:27:49 -0700
committerPalmer Dabbelt <palmer@rivosinc.com>2024-10-24 14:12:59 -0700
commit3c2e0aff7b4f03fbc11b7d63c8db5b94a48978cf (patch)
treebde1ba52aad93d082306f2bc845b6010a9871c94
parent7470b5afd150e683c7aef03961d0c4c6f500de3b (diff)
riscv: hwprobe: Export the Supm ISA extension
Supm is a virtual ISA extension defined in the RISC-V Pointer Masking specification, which indicates that pointer masking is available in U-mode. It can be provided by either Smnpm or Ssnpm, depending on which mode the kernel runs in. Userspace should not care about this distinction, so export Supm instead of either underlying extension. Hide the extension if the kernel was compiled without support for the pointer masking prctl() interface. Signed-off-by: Samuel Holland <samuel.holland@sifive.com> Link: https://lore.kernel.org/r/20241016202814.4061541-9-samuel.holland@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
-rw-r--r--Documentation/arch/riscv/hwprobe.rst3
-rw-r--r--arch/riscv/include/uapi/asm/hwprobe.h1
-rw-r--r--arch/riscv/kernel/sys_hwprobe.c3
3 files changed, 7 insertions, 0 deletions
diff --git a/Documentation/arch/riscv/hwprobe.rst b/Documentation/arch/riscv/hwprobe.rst
index 85b709257918..b9aec2e5bbd4 100644
--- a/Documentation/arch/riscv/hwprobe.rst
+++ b/Documentation/arch/riscv/hwprobe.rst
@@ -239,6 +239,9 @@ The following keys are defined:
ratified in commit 98918c844281 ("Merge pull request #1217 from
riscv/zawrs") of riscv-isa-manual.
+ * :c:macro:`RISCV_HWPROBE_EXT_SUPM`: The Supm extension is supported as
+ defined in version 1.0 of the RISC-V Pointer Masking extensions.
+
* :c:macro:`RISCV_HWPROBE_KEY_CPUPERF_0`: Deprecated. Returns similar values to
:c:macro:`RISCV_HWPROBE_KEY_MISALIGNED_SCALAR_PERF`, but the key was
mistakenly classified as a bitmask rather than a value.
diff --git a/arch/riscv/include/uapi/asm/hwprobe.h b/arch/riscv/include/uapi/asm/hwprobe.h
index 1e153cda57db..868ff41b93d6 100644
--- a/arch/riscv/include/uapi/asm/hwprobe.h
+++ b/arch/riscv/include/uapi/asm/hwprobe.h
@@ -72,6 +72,7 @@ struct riscv_hwprobe {
#define RISCV_HWPROBE_EXT_ZCF (1ULL << 46)
#define RISCV_HWPROBE_EXT_ZCMOP (1ULL << 47)
#define RISCV_HWPROBE_EXT_ZAWRS (1ULL << 48)
+#define RISCV_HWPROBE_EXT_SUPM (1ULL << 49)
#define RISCV_HWPROBE_KEY_CPUPERF_0 5
#define RISCV_HWPROBE_MISALIGNED_UNKNOWN (0 << 0)
#define RISCV_HWPROBE_MISALIGNED_EMULATED (1 << 0)
diff --git a/arch/riscv/kernel/sys_hwprobe.c b/arch/riscv/kernel/sys_hwprobe.c
index cea0ca2bf2a2..0ac78e9f7c94 100644
--- a/arch/riscv/kernel/sys_hwprobe.c
+++ b/arch/riscv/kernel/sys_hwprobe.c
@@ -150,6 +150,9 @@ static void hwprobe_isa_ext0(struct riscv_hwprobe *pair,
EXT_KEY(ZFH);
EXT_KEY(ZFHMIN);
}
+
+ if (IS_ENABLED(CONFIG_RISCV_ISA_SUPM))
+ EXT_KEY(SUPM);
#undef EXT_KEY
}