Re: [PATCH, RFC 43/62] syscall/x86: Wire up a system call for MKTME encryption keys

From: Mike Rapoport
Date: Wed May 29 2019 - 03:25:15 EST


On Wed, May 08, 2019 at 05:44:03PM +0300, Kirill A. Shutemov wrote:
> From: Alison Schofield <alison.schofield@xxxxxxxxx>
>
> encrypt_mprotect() is a new system call to support memory encryption.
>
> It takes the same parameters as legacy mprotect, plus an additional
> key serial number that is mapped to an encryption keyid.

Shouldn't this patch be after the encrypt_mprotect() is added?

> Signed-off-by: Alison Schofield <alison.schofield@xxxxxxxxx>
> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
> ---
> arch/x86/entry/syscalls/syscall_32.tbl | 1 +
> arch/x86/entry/syscalls/syscall_64.tbl | 1 +
> include/linux/syscalls.h | 2 ++
> include/uapi/asm-generic/unistd.h | 4 +++-
> kernel/sys_ni.c | 2 ++
> 5 files changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl
> index 1f9607ed087c..dbcd4c28d743 100644
> --- a/arch/x86/entry/syscalls/syscall_32.tbl
> +++ b/arch/x86/entry/syscalls/syscall_32.tbl
> @@ -433,3 +433,4 @@
> 425 i386 io_uring_setup sys_io_uring_setup __ia32_sys_io_uring_setup
> 426 i386 io_uring_enter sys_io_uring_enter __ia32_sys_io_uring_enter
> 427 i386 io_uring_register sys_io_uring_register __ia32_sys_io_uring_register
> +428 i386 encrypt_mprotect sys_encrypt_mprotect __ia32_sys_encrypt_mprotect
> diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl
> index 92ee0b4378d4..d01bd132e9ee 100644
> --- a/arch/x86/entry/syscalls/syscall_64.tbl
> +++ b/arch/x86/entry/syscalls/syscall_64.tbl
> @@ -349,6 +349,7 @@
> 425 common io_uring_setup __x64_sys_io_uring_setup
> 426 common io_uring_enter __x64_sys_io_uring_enter
> 427 common io_uring_register __x64_sys_io_uring_register
> +428 common encrypt_mprotect __x64_sys_encrypt_mprotect
>
> #
> # x32-specific system call numbers start at 512 to avoid cache impact
> diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
> index e446806a561f..38a2d7b95397 100644
> --- a/include/linux/syscalls.h
> +++ b/include/linux/syscalls.h
> @@ -988,6 +988,8 @@ asmlinkage long sys_rseq(struct rseq __user *rseq, uint32_t rseq_len,
> asmlinkage long sys_pidfd_send_signal(int pidfd, int sig,
> siginfo_t __user *info,
> unsigned int flags);
> +asmlinkage long sys_encrypt_mprotect(unsigned long start, size_t len,
> + unsigned long prot, key_serial_t serial);
>
> /*
> * Architecture-specific system calls
> diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h
> index dee7292e1df6..86f942f54b1b 100644
> --- a/include/uapi/asm-generic/unistd.h
> +++ b/include/uapi/asm-generic/unistd.h
> @@ -832,9 +832,11 @@ __SYSCALL(__NR_io_uring_setup, sys_io_uring_setup)
> __SYSCALL(__NR_io_uring_enter, sys_io_uring_enter)
> #define __NR_io_uring_register 427
> __SYSCALL(__NR_io_uring_register, sys_io_uring_register)
> +#define __NR_encrypt_mprotect 428
> +__SYSCALL(__NR_encrypt_mprotect, sys_encrypt_mprotect)
>
> #undef __NR_syscalls
> -#define __NR_syscalls 428
> +#define __NR_syscalls 429
>
> /*
> * 32 bit systems traditionally used different
> diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
> index d21f4befaea4..80da8d9ac8b1 100644
> --- a/kernel/sys_ni.c
> +++ b/kernel/sys_ni.c
> @@ -350,6 +350,8 @@ COND_SYSCALL(pkey_mprotect);
> COND_SYSCALL(pkey_alloc);
> COND_SYSCALL(pkey_free);
>
> +/* multi-key total memory encryption keys */
> +COND_SYSCALL(encrypt_mprotect);
>
> /*
> * Architecture specific weak syscall entries.
> --
> 2.20.1
>

--
Sincerely yours,
Mike.