diff options
| author |   Ivy Lopez <skunkolee@gmail.com> | 2026-08-31 19:37:46 -0600 |
|---|---|---|
| committer |   Paul Walmsley <pjw@kernel.org> | 2026-09-01 19:20:13 -0600 |
| commit | 93a27367bacdc32e2cdb478597102175db3fb80c (patch) | |
| tree | 9660edd64bf2883d323ac4af57b1a91bcc8ab19a | |
| parent | perf: RISC-V: check cpu_hw_evt before dereference in overflow IRQ (diff) | |
riscv: hwprobe: simplify has_fpu() to check D extension only
The kernel never supports D without F, since D depends on F. The
D-extension flag is cleared during devicetree/ACPI parsing whenever
F is not present, so has_fpu() checking either extension with '||'
never actually produces a different result than checking D alone -
F without D cannot occur in practice, and there is no observable
impact on RISCV_HWPROBE_IMA_FD or userspace.
Simplify has_fpu() to check D only, matching the expectations set
elsewhere in the kernel for this dependency, rather than relying on
a redundant OR condition.
sys_hwprobe.c already calls has_fpu() and needs no changes.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=221874
Suggested-by: Conor Dooley <conor.dooley@microchip.com>
Suggested-by: Andreas Schwab <schwab@suse.de>
Signed-off-by: Ivy Lopez <skunkolee@gmail.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://patch.msgid.link/20260901013746.19386-1-skunkolee@gmail.com
[pjw@kernel.org: updated to apply]
Signed-off-by: Paul Walmsley <pjw@kernel.org>
| -rw-r--r-- | arch/riscv/include/asm/switch_to.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/riscv/include/asm/switch_to.h b/arch/riscv/include/asm/switch_to.h index 04f10a949066..123c89b694e8 100644 --- a/arch/riscv/include/asm/switch_to.h +++ b/arch/riscv/include/asm/switch_to.h @@ -61,8 +61,8 @@ static inline void __switch_to_fpu(struct task_struct *prev, static __always_inline bool has_fpu(void) { - return riscv_has_extension_likely(RISCV_ISA_EXT_F) || - riscv_has_extension_likely(RISCV_ISA_EXT_D); + /* D extension depends on F, so checking D alone is sufficient. */ + return riscv_has_extension_likely(RISCV_ISA_EXT_D); } #else static __always_inline bool has_fpu(void) { return false; } |