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| author | Mark Brown <broonie@kernel.org> | 2024-10-02 01:58:49 +0300 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2024-10-04 14:04:34 +0300 |
| commit | d0aa2b4351862cc2ce8d97e00c96bffc02ea16af (patch) | |
| tree | 2d0e6b77b585766bc51820eb67a7eb52b37cbaa6 /arch/arm64/include/asm | |
| parent | dad947cc22cff28348d04e21fa4d6c882385fd7d (diff) | |
| download | linux-d0aa2b4351862cc2ce8d97e00c96bffc02ea16af.tar.xz | |
arm64/gcs: Provide put_user_gcs()
In order for EL1 to write to an EL0 GCS it must use the GCSSTTR instruction
rather than a normal STTR. Provide a put_user_gcs() which does this.
Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20241001-arm64-gcs-v13-10-222b78d87eee@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/include/asm')
| -rw-r--r-- | arch/arm64/include/asm/uaccess.h | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h index 0db494b24dd0..5b91803201ef 100644 --- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -522,6 +522,24 @@ static inline int gcssttr(unsigned long __user *addr, unsigned long val) return err; } +static inline void put_user_gcs(unsigned long val, unsigned long __user *addr, + int *err) +{ + int ret; + + if (!access_ok((char __user *)addr, sizeof(u64))) { + *err = -EFAULT; + return; + } + + uaccess_ttbr0_enable(); + ret = gcssttr(addr, val); + if (ret != 0) + *err = ret; + uaccess_ttbr0_disable(); +} + + #endif /* CONFIG_ARM64_GCS */ #endif /* __ASM_UACCESS_H */ |