On Thu, 2020-12-03 at 08:29 +0200, Mike Rapoport wrote: > From: Mike Rapoport <rppt@xxxxxxxxxxxxx> > > Wire up memfd_secret system call on architectures that define > ARCH_HAS_SET_DIRECT_MAP, namely arm64, risc-v and x86. > > Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx> > Acked-by: Palmer Dabbelt <palmerdabbelt@xxxxxxxxxx> > Acked-by: Arnd Bergmann <arnd@xxxxxxxx> > --- > arch/arm64/include/uapi/asm/unistd.h | 1 + > arch/riscv/include/asm/unistd.h | 1 + > arch/x86/entry/syscalls/syscall_32.tbl | 1 + > arch/x86/entry/syscalls/syscall_64.tbl | 1 + > include/linux/syscalls.h | 1 + > include/uapi/asm-generic/unistd.h | 6 +++++- > mm/secretmem.c | 3 +++ > scripts/checksyscalls.sh | 4 ++++ > 8 files changed, 17 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/include/uapi/asm/unistd.h b/arch/arm64/include/uapi/asm/unistd.h > index f83a70e07df8..ce2ee8f1e361 100644 > --- a/arch/arm64/include/uapi/asm/unistd.h > +++ b/arch/arm64/include/uapi/asm/unistd.h > @@ -20,5 +20,6 @@ > #define __ARCH_WANT_SET_GET_RLIMIT > #define __ARCH_WANT_TIME32_SYSCALLS > #define __ARCH_WANT_SYS_CLONE3 > +#define __ARCH_WANT_MEMFD_SECRET > > #include <asm-generic/unistd.h> > diff --git a/arch/riscv/include/asm/unistd.h b/arch/riscv/include/asm/unistd.h > index 977ee6181dab..6c316093a1e5 100644 > --- a/arch/riscv/include/asm/unistd.h > +++ b/arch/riscv/include/asm/unistd.h > @@ -9,6 +9,7 @@ > */ > > #define __ARCH_WANT_SYS_CLONE > +#define __ARCH_WANT_MEMFD_SECRET > > #include <uapi/asm/unistd.h> > > diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl > index c52ab1c4a755..109e6681b8fa 100644 > --- a/arch/x86/entry/syscalls/syscall_32.tbl > +++ b/arch/x86/entry/syscalls/syscall_32.tbl > @@ -446,3 +446,4 @@ > 439 i386 faccessat2 sys_faccessat2 > 440 i386 process_madvise sys_process_madvise > 441 i386 watch_mount sys_watch_mount > +442 i386 memfd_secret sys_memfd_secret > diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl > index f3270a9ef467..742cf17d7725 100644 > --- a/arch/x86/entry/syscalls/syscall_64.tbl > +++ b/arch/x86/entry/syscalls/syscall_64.tbl > @@ -363,6 +363,7 @@ > 439 common faccessat2 sys_faccessat2 > 440 common process_madvise sys_process_madvise > 441 common watch_mount sys_watch_mount > +442 common memfd_secret sys_memfd_secret > > # > # Due to a historical design error, certain syscalls are numbered differently > diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h > index 6d55324363ab..f9d93fbf9b69 100644 > --- a/include/linux/syscalls.h > +++ b/include/linux/syscalls.h > @@ -1010,6 +1010,7 @@ asmlinkage long sys_pidfd_send_signal(int pidfd, int sig, > asmlinkage long sys_pidfd_getfd(int pidfd, int fd, unsigned int flags); > asmlinkage long sys_watch_mount(int dfd, const char __user *path, > unsigned int at_flags, int watch_fd, int watch_id); > +asmlinkage long sys_memfd_secret(unsigned long flags); > > /* > * Architecture-specific system calls > diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h > index 5df46517260e..51151888f330 100644 > --- a/include/uapi/asm-generic/unistd.h > +++ b/include/uapi/asm-generic/unistd.h > @@ -861,9 +861,13 @@ __SYSCALL(__NR_faccessat2, sys_faccessat2) > __SYSCALL(__NR_process_madvise, sys_process_madvise) > #define __NR_watch_mount 441 > __SYSCALL(__NR_watch_mount, sys_watch_mount) > +#ifdef __ARCH_WANT_MEMFD_SECRET > +#define __NR_memfd_secret 442 > +__SYSCALL(__NR_memfd_secret, sys_memfd_secret) > +#endif I can't see where was it defined for arm64 after it looks like Andrew has deleted the above chunk. Thus, we have a warning using this .config: https://cailca.coding.net/public/linux/mm/git/files/master/arm64.config <stdin>:1539:2: warning: #warning syscall memfd_secret not implemented [-Wcpp] > > #undef __NR_syscalls > -#define __NR_syscalls 442 > +#define __NR_syscalls 443 > > /* > * 32 bit systems traditionally used different > diff --git a/mm/secretmem.c b/mm/secretmem.c > index 7236f4d9458a..b8a32954ac68 100644 > --- a/mm/secretmem.c > +++ b/mm/secretmem.c > @@ -415,6 +415,9 @@ static int __init secretmem_setup(char *str) > unsigned long reserved_size; > int err; > > + if (!can_set_direct_map()) > + return 0; > + > reserved_size = memparse(str, NULL); > if (!reserved_size) > return 0; > diff --git a/scripts/checksyscalls.sh b/scripts/checksyscalls.sh > index a18b47695f55..b7609958ee36 100755 > --- a/scripts/checksyscalls.sh > +++ b/scripts/checksyscalls.sh > @@ -40,6 +40,10 @@ cat << EOF > #define __IGNORE_setrlimit /* setrlimit */ > #endif > > +#ifndef __ARCH_WANT_MEMFD_SECRET > +#define __IGNORE_memfd_secret > +#endif > + > /* Missing flags argument */ > #define __IGNORE_renameat /* renameat2 */ >