[v2,07/29] ARM: add kexec_file_load system call number

Message ID 20190118161835.2259170-8-arnd@arndb.de
State Accepted
Commit 4ab65ba7a5cbad47520274d88d066bf8eb83f161
Headers show
Series
  • y2038: add time64 syscalls
Related show

Commit Message

Arnd Bergmann Jan. 18, 2019, 4:18 p.m.
A couple of architectures including arm64 already implement the
kexec_file_load system call, on many others we have assigned a system
call number for it, but not implemented it yet.

Adding the number in arch/arm/ lets us use the system call on arm64
systems in compat mode, and also reduces the number of differences
between architectures. If we want to implement kexec_file_load on ARM
in the future, the number assignment means that kexec tools can already
be built with the now current set of kernel headers.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

---
 arch/arm/tools/syscall.tbl        | 1 +
 arch/arm64/include/asm/unistd.h   | 2 +-
 arch/arm64/include/asm/unistd32.h | 2 ++
 3 files changed, 4 insertions(+), 1 deletion(-)

-- 
2.20.0

Comments

Russell King - ARM Linux admin Jan. 25, 2019, 4:21 p.m. | #1
On Fri, Jan 25, 2019 at 03:43:59PM +0000, Catalin Marinas wrote:
> On Fri, Jan 18, 2019 at 05:18:13PM +0100, Arnd Bergmann wrote:

> > diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl

> > index 86de9eb34296..20ed7e026723 100644

> > --- a/arch/arm/tools/syscall.tbl

> > +++ b/arch/arm/tools/syscall.tbl

> > @@ -415,3 +415,4 @@

> >  398	common	rseq			sys_rseq

> >  399	common	io_pgetevents		sys_io_pgetevents

> >  400	common	migrate_pages		sys_migrate_pages

> > +401	common	kexec_file_load		sys_kexec_file_load

> 

> I presume on arm32 this would still return -ENOSYS.


Yes, I already checked.  If CONFIG_KEXEC_FILE is not set, then
kernel/kexec_file.c is not built, and we fall back to the stub
in kernel/sys_ni.c.

-- 
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Patch

diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl
index 86de9eb34296..20ed7e026723 100644
--- a/arch/arm/tools/syscall.tbl
+++ b/arch/arm/tools/syscall.tbl
@@ -415,3 +415,4 @@ 
 398	common	rseq			sys_rseq
 399	common	io_pgetevents		sys_io_pgetevents
 400	common	migrate_pages		sys_migrate_pages
+401	common	kexec_file_load		sys_kexec_file_load
diff --git a/arch/arm64/include/asm/unistd.h b/arch/arm64/include/asm/unistd.h
index 261216c3336e..2c30e6f145ff 100644
--- a/arch/arm64/include/asm/unistd.h
+++ b/arch/arm64/include/asm/unistd.h
@@ -44,7 +44,7 @@ 
 #define __ARM_NR_compat_set_tls		(__ARM_NR_COMPAT_BASE + 5)
 #define __ARM_NR_COMPAT_END		(__ARM_NR_COMPAT_BASE + 0x800)
 
-#define __NR_compat_syscalls		401
+#define __NR_compat_syscalls		402
 #endif
 
 #define __ARCH_WANT_SYS_CLONE
diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/unistd32.h
index f15bcbacb8f6..8ca1d4c304f4 100644
--- a/arch/arm64/include/asm/unistd32.h
+++ b/arch/arm64/include/asm/unistd32.h
@@ -823,6 +823,8 @@  __SYSCALL(__NR_rseq, sys_rseq)
 __SYSCALL(__NR_io_pgetevents, compat_sys_io_pgetevents)
 #define __NR_migrate_pages 400
 __SYSCALL(__NR_migrate_pages, compat_sys_migrate_pages)
+#define __NR_kexec_file_load 401
+__SYSCALL(__NR_kexec_file_load, sys_kexec_file_load)
 
 /*
  * Please add new compat syscalls above this comment and update