[PATCH RFC 5/7] arch: hookup fchroot() system call
From: Christian Brauner <brauner@kernel.org>
Date: 2026-07-23 11:30:54
Also in:
linux-doc, linux-fsdevel, lkml
Subsystem:
alpha port, arm port, arm64 port (aarch64 architecture), generic include/asm header files, linux for powerpc (32-bit and 64-bit), m68k architecture, microblaze architecture, mips, parisc architecture, s390 architecture, sparc + ultrasparc (sparc/sparc64), superh, tensilica xtensa port (xtensa), the rest, x86 architecture (32-bit and 64-bit), x86 entry code · Maintainers:
Richard Henderson, Matt Turner, Magnus Lindholm, Russell King, Catalin Marinas, Will Deacon, Arnd Bergmann, Madhavan Srinivasan, Michael Ellerman, Geert Uytterhoeven, Michal Simek, Thomas Bogendoerfer, "James E.J. Bottomley", Helge Deller, Heiko Carstens, Vasily Gorbik, Alexander Gordeev, "David S. Miller", Andreas Larsson, Yoshinori Sato, Rich Felker, John Paul Adrian Glaubitz, Chris Zankel, Max Filippov, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen, Andy Lutomirski
Wire up the fchroot() system call as number 472 on (nearly) all architectures. Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org> --- arch/alpha/kernel/syscalls/syscall.tbl | 1 + arch/arm/tools/syscall.tbl | 1 + arch/arm64/tools/syscall_32.tbl | 1 + arch/m68k/kernel/syscalls/syscall.tbl | 1 + arch/microblaze/kernel/syscalls/syscall.tbl | 1 + arch/mips/kernel/syscalls/syscall_n32.tbl | 1 + arch/mips/kernel/syscalls/syscall_n64.tbl | 1 + arch/mips/kernel/syscalls/syscall_o32.tbl | 1 + arch/parisc/kernel/syscalls/syscall.tbl | 1 + arch/powerpc/kernel/syscalls/syscall.tbl | 1 + arch/s390/kernel/syscalls/syscall.tbl | 1 + arch/sh/kernel/syscalls/syscall.tbl | 1 + arch/sparc/kernel/syscalls/syscall.tbl | 1 + arch/x86/entry/syscalls/syscall_32.tbl | 1 + arch/x86/entry/syscalls/syscall_64.tbl | 1 + arch/xtensa/kernel/syscalls/syscall.tbl | 1 + include/uapi/asm-generic/unistd.h | 6 +++++- scripts/syscall.tbl | 1 + 18 files changed, 22 insertions(+), 1 deletion(-)
diff --git a/arch/alpha/kernel/syscalls/syscall.tbl b/arch/alpha/kernel/syscalls/syscall.tbl
index f31b7afffc34..52e3538cc7df 100644
--- a/arch/alpha/kernel/syscalls/syscall.tbl
+++ b/arch/alpha/kernel/syscalls/syscall.tbl@@ -511,3 +511,4 @@ 579 common file_setattr sys_file_setattr 580 common listns sys_listns 581 common rseq_slice_yield sys_rseq_slice_yield +582 common fchroot sys_fchroot
diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl
index 94351e22bfcf..55717ed32c27 100644
--- a/arch/arm/tools/syscall.tbl
+++ b/arch/arm/tools/syscall.tbl@@ -486,3 +486,4 @@ 469 common file_setattr sys_file_setattr 470 common listns sys_listns 471 common rseq_slice_yield sys_rseq_slice_yield +472 common fchroot sys_fchroot
diff --git a/arch/arm64/tools/syscall_32.tbl b/arch/arm64/tools/syscall_32.tbl
index 62d93d88e0fe..df2d1d82fb3c 100644
--- a/arch/arm64/tools/syscall_32.tbl
+++ b/arch/arm64/tools/syscall_32.tbl@@ -483,3 +483,4 @@ 469 common file_setattr sys_file_setattr 470 common listns sys_listns 471 common rseq_slice_yield sys_rseq_slice_yield +472 common fchroot sys_fchroot
diff --git a/arch/m68k/kernel/syscalls/syscall.tbl b/arch/m68k/kernel/syscalls/syscall.tbl
index 248934257101..ba7a4d8903d0 100644
--- a/arch/m68k/kernel/syscalls/syscall.tbl
+++ b/arch/m68k/kernel/syscalls/syscall.tbl@@ -471,3 +471,4 @@ 469 common file_setattr sys_file_setattr 470 common listns sys_listns 471 common rseq_slice_yield sys_rseq_slice_yield +472 common fchroot sys_fchroot
diff --git a/arch/microblaze/kernel/syscalls/syscall.tbl b/arch/microblaze/kernel/syscalls/syscall.tbl
index 223d26303627..c55a5c96f49b 100644
--- a/arch/microblaze/kernel/syscalls/syscall.tbl
+++ b/arch/microblaze/kernel/syscalls/syscall.tbl@@ -477,3 +477,4 @@ 469 common file_setattr sys_file_setattr 470 common listns sys_listns 471 common rseq_slice_yield sys_rseq_slice_yield +472 common fchroot sys_fchroot
diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl
index 7430714e2b8f..9ae88e4eac61 100644
--- a/arch/mips/kernel/syscalls/syscall_n32.tbl
+++ b/arch/mips/kernel/syscalls/syscall_n32.tbl@@ -410,3 +410,4 @@ 469 n32 file_setattr sys_file_setattr 470 n32 listns sys_listns 471 n32 rseq_slice_yield sys_rseq_slice_yield +472 n32 fchroot sys_fchroot
diff --git a/arch/mips/kernel/syscalls/syscall_n64.tbl b/arch/mips/kernel/syscalls/syscall_n64.tbl
index 630aab9e5425..83dc93a0712f 100644
--- a/arch/mips/kernel/syscalls/syscall_n64.tbl
+++ b/arch/mips/kernel/syscalls/syscall_n64.tbl@@ -386,3 +386,4 @@ 469 n64 file_setattr sys_file_setattr 470 n64 listns sys_listns 471 n64 rseq_slice_yield sys_rseq_slice_yield +472 n64 fchroot sys_fchroot
diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl
index 128653112284..9c62429c9b7b 100644
--- a/arch/mips/kernel/syscalls/syscall_o32.tbl
+++ b/arch/mips/kernel/syscalls/syscall_o32.tbl@@ -459,3 +459,4 @@ 469 o32 file_setattr sys_file_setattr 470 o32 listns sys_listns 471 o32 rseq_slice_yield sys_rseq_slice_yield +472 o32 fchroot sys_fchroot
diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl
index c6331dad9461..88adc4016cce 100644
--- a/arch/parisc/kernel/syscalls/syscall.tbl
+++ b/arch/parisc/kernel/syscalls/syscall.tbl@@ -470,3 +470,4 @@ 469 common file_setattr sys_file_setattr 470 common listns sys_listns 471 common rseq_slice_yield sys_rseq_slice_yield +472 common fchroot sys_fchroot
diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl
index 4fcc7c58a105..cfbb70039ff0 100644
--- a/arch/powerpc/kernel/syscalls/syscall.tbl
+++ b/arch/powerpc/kernel/syscalls/syscall.tbl@@ -562,3 +562,4 @@ 469 common file_setattr sys_file_setattr 470 common listns sys_listns 471 nospu rseq_slice_yield sys_rseq_slice_yield +472 common fchroot sys_fchroot
diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl
index 09a7ef04d979..1b45e68a217b 100644
--- a/arch/s390/kernel/syscalls/syscall.tbl
+++ b/arch/s390/kernel/syscalls/syscall.tbl@@ -398,3 +398,4 @@ 469 common file_setattr sys_file_setattr 470 common listns sys_listns 471 common rseq_slice_yield sys_rseq_slice_yield +472 common fchroot sys_fchroot
diff --git a/arch/sh/kernel/syscalls/syscall.tbl b/arch/sh/kernel/syscalls/syscall.tbl
index 70b315cbe710..ace068dff0de 100644
--- a/arch/sh/kernel/syscalls/syscall.tbl
+++ b/arch/sh/kernel/syscalls/syscall.tbl@@ -475,3 +475,4 @@ 469 common file_setattr sys_file_setattr 470 common listns sys_listns 471 common rseq_slice_yield sys_rseq_slice_yield +472 common fchroot sys_fchroot
diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/syscalls/syscall.tbl
index 7e71bf7fcd14..5b9fe0e8140f 100644
--- a/arch/sparc/kernel/syscalls/syscall.tbl
+++ b/arch/sparc/kernel/syscalls/syscall.tbl@@ -517,3 +517,4 @@ 469 common file_setattr sys_file_setattr 470 common listns sys_listns 471 common rseq_slice_yield sys_rseq_slice_yield +472 common fchroot sys_fchroot
diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl
index f832ebd2d79b..2c172ef48dfd 100644
--- a/arch/x86/entry/syscalls/syscall_32.tbl
+++ b/arch/x86/entry/syscalls/syscall_32.tbl@@ -477,3 +477,4 @@ 469 i386 file_setattr sys_file_setattr 470 i386 listns sys_listns 471 i386 rseq_slice_yield sys_rseq_slice_yield +472 i386 fchroot sys_fchroot
diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl
index 524155d655da..d5b6045b0090 100644
--- a/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/arch/x86/entry/syscalls/syscall_64.tbl@@ -396,6 +396,7 @@ 469 common file_setattr sys_file_setattr 470 common listns sys_listns 471 common rseq_slice_yield sys_rseq_slice_yield +472 common fchroot sys_fchroot # # Due to a historical design error, certain syscalls are numbered differently
diff --git a/arch/xtensa/kernel/syscalls/syscall.tbl b/arch/xtensa/kernel/syscalls/syscall.tbl
index a9bca4e484de..d354bb231796 100644
--- a/arch/xtensa/kernel/syscalls/syscall.tbl
+++ b/arch/xtensa/kernel/syscalls/syscall.tbl@@ -442,3 +442,4 @@ 469 common file_setattr sys_file_setattr 470 common listns sys_listns 471 common rseq_slice_yield sys_rseq_slice_yield +472 common fchroot sys_fchroot
diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h
index a627acc8fb5f..5b7e77a7c736 100644
--- a/include/uapi/asm-generic/unistd.h
+++ b/include/uapi/asm-generic/unistd.h@@ -863,8 +863,12 @@ __SYSCALL(__NR_listns, sys_listns) #define __NR_rseq_slice_yield 471 __SYSCALL(__NR_rseq_slice_yield, sys_rseq_slice_yield) +/* fs/open.c */ +#define __NR_fchroot 472 +__SYSCALL(__NR_fchroot, sys_fchroot) + #undef __NR_syscalls -#define __NR_syscalls 472 +#define __NR_syscalls 473 /* * 32 bit systems traditionally used different
diff --git a/scripts/syscall.tbl b/scripts/syscall.tbl
index 7a42b32b6577..0ab531605120 100644
--- a/scripts/syscall.tbl
+++ b/scripts/syscall.tbl@@ -412,3 +412,4 @@ 469 common file_setattr sys_file_setattr 470 common listns sys_listns 471 common rseq_slice_yield sys_rseq_slice_yield +472 common fchroot sys_fchroot
--
2.53.0