From: Christian Brauner <brauner@kernel.org>
To: linux-fsdevel@vger.kernel.org, Andy Lutomirski <luto@kernel.org>,
Jann Horn <jannh@google.com>
Cc: John Ericson <mail@johnericson.me>,
linux-api@vger.kernel.org, "H. Peter Anvin" <hpa@zytor.com>,
Kees Cook <kees@kernel.org>,
Farid Zakaria <farid.m.zakaria@gmail.com>,
Alexander Viro <viro@zeniv.linux.org.uk>,
Christian Brauner <brauner@kernel.org>, Jan Kara <jack@suse.cz>,
linux-kernel@vger.kernel.org, Jonathan Corbet <corbet@lwn.net>,
linux-doc@vger.kernel.org
Subject: [PATCH RFC 5/7] arch: hookup fchroot() system call
Date: Thu, 23 Jul 2026 13:30:24 +0200 [thread overview]
Message-ID: <20260723-work-failfs-v1-5-3f69b9a9e958@kernel.org> (raw)
In-Reply-To: <20260723-work-failfs-v1-0-3f69b9a9e958@kernel.org>
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
next prev parent reply other threads:[~2026-07-23 11:30 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-07-23 11:30 [PATCH RFC 0/7] fs: add failfs Christian Brauner
2026-07-23 11:30 ` [PATCH RFC 1/7] " Christian Brauner
2026-07-23 11:30 ` [PATCH RFC 2/7] fs: add FD_FAILFS_ROOT and support it in fchdir() Christian Brauner
2026-07-23 11:30 ` [PATCH RFC 3/7] fs: add fchroot() Christian Brauner
2026-07-23 11:30 ` [PATCH RFC 4/7] fs: support FD_FAILFS_ROOT in fchroot() Christian Brauner
2026-07-23 12:49 ` Andy Lutomirski
2026-07-23 13:01 ` Christian Brauner
2026-07-23 13:50 ` Andy Lutomirski
2026-07-23 14:35 ` Christian Brauner
2026-07-23 16:59 ` Andy Lutomirski
2026-07-23 14:42 ` Jann Horn
2026-07-23 14:07 ` Jann Horn
2026-07-23 16:56 ` Andy Lutomirski
2026-07-23 11:30 ` Christian Brauner [this message]
2026-07-23 11:30 ` [PATCH RFC 6/7] selftests/filesystems: add failfs selftests Christian Brauner
2026-07-23 11:30 ` [PATCH RFC 7/7] Documentation: add failfs documentation Christian Brauner
2026-07-23 14:04 ` Miquel Sabaté Solà
2026-07-23 12:53 ` [PATCH RFC 0/7] fs: add failfs Andy Lutomirski
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