Re: [PATCH RFC 2/3] riscv: Add Svukte extension support

From: Deepak Gupta
Date: Tue Oct 29 2024 - 15:30:12 EST


On Fri, Sep 20, 2024 at 03:39:04PM +0800, Max Hsu wrote:
Svukte extension introduce senvcfg.UKTE, hstatus.HUKTE.

This patch add CSR bit definition, and detects if Svukte ISA extension
is available, cpufeature will set the correspond bit field so the
svukte-qualified memory accesses are protected in a manner that is
timing-independent of the faulting virtual address.

Since hstatus.HU is not enabled by linux, enabling hstatus.HUKTE will
not be affective.

This patch depends on patch "riscv: Per-thread envcfg CSR support" [1]

Link: https://lore.kernel.org/linux-riscv/20240814081126.956287-1-samuel.holland@xxxxxxxxxx/ [1]

Reviewed-by: Samuel Holland <samuel.holland@xxxxxxxxxx>
Signed-off-by: Max Hsu <max.hsu@xxxxxxxxxx>
---
arch/riscv/include/asm/csr.h | 2 ++
arch/riscv/include/asm/hwcap.h | 1 +
arch/riscv/kernel/cpufeature.c | 4 ++++
3 files changed, 7 insertions(+)

Reviewed-by: Deepak Gupta <debug@xxxxxxxxxxxx>