From nobody Tue Feb 10 07:40:35 2026 Received: from smtp-out3.simply.com (smtp-out3.simply.com [94.231.106.210]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5DA0833A03F; Fri, 16 Jan 2026 15:30:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=94.231.106.210 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768577461; cv=none; b=QA2ObTyIoTUh2tVHLTVSQfEesJfd1E3bUIb5Ed7TOg7udcZl1OfgUIXCN4+xtgftVwbBDNjJ2rhoRc8BumEySR0e4yHYXO3BrQuRg3VClQ+rUe09Bw5TVIVcpNa1zOMHp7e+ADuIven52umSNSnvtOPTCYlFByIlmDvkwm1k4KM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768577461; c=relaxed/simple; bh=IpZZ8A/8vRhXhWckaz1NwuJhiZ+fEaPg96F8nlsuS2g=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=oJ2d/hvx8/YLm/bT9AlFgCSZxZakFkTPJKDAL2MBj7/PyJ6GbQyHvRQiHOMLueCMc/Un1wSM/CRvGB25Kevzoel1pDsjB7TwagmA6IKeu2yqnqc2mIwGPmQ71Vcc4N3I3BRCJVNyAitTAO/jNheol7VW52MB3PfP/SVgB3SOMaQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gaisler.com; spf=pass smtp.mailfrom=gaisler.com; dkim=fail (0-bit key) header.d=gaisler.com header.i=@gaisler.com header.b=Qdj1nn/b reason="key not found in DNS"; arc=none smtp.client-ip=94.231.106.210 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gaisler.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gaisler.com Authentication-Results: smtp.subspace.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=gaisler.com header.i=@gaisler.com header.b="Qdj1nn/b" Received: from localhost (localhost [127.0.0.1]) by smtp.simply.com (Simply.com) with ESMTP id 4dt3hr0nRHz1FQVr; Fri, 16 Jan 2026 16:30:52 +0100 (CET) Received: from ludwig.got.gaisler.com (h-98-128-223-123.NA.cust.bahnhof.se [98.128.223.123]) by smtp.simply.com (Simply.com) with ESMTPA id 4dt3hq5dslz1DDFM; Fri, 16 Jan 2026 16:30:51 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gaisler.com; s=simplycom2; t=1768577452; bh=4g2nxBOyYfkdzGSQ0inwR35X22JbYjY4qn7TdUVrjIU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Qdj1nn/b/Qi4pkVeDE3zMn/TjSMs/38o958jz6eojkiSlCGfLFeuCn9ql6XnzJ2SQ 9/89I6jOWkzv0igZaMK7bH8aruIToM4IOEMyRdcKYgmtO9UzVPEe2wf8HbIYpVAjkM 5fQRbuF0sGAYH6rzmzEFeZ3LGOC5WKLTM/HR20bnp0cpiyKx0P4+vN1UaVYKA6Cy/d sVHeEhv/RpgPPP+JnGKsuyWose8BguuRxBd4dVXJ6u4g3fr3icn1l82nIzT0Bx7Iom KHSXs0yDzYdIwHDegvFo2NcTQRNqOg6cw8L+jyP8y0LpxzYVFVPMzqCAssRYrk7lBL SCer2MFSJa7oQ== From: Ludwig Rydberg To: davem@davemloft.net, andreas@gaisler.com, brauner@kernel.org, shuah@kernel.org Cc: sparclinux@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, arnd@arndb.de, glaubitz@physik.fu-berlin.de, geert@linux-m68k.org, schuster.simon@siemens-energy.com Subject: [PATCH 2/3] sparc: Add architecture support for clone3 Date: Fri, 16 Jan 2026 16:30:50 +0100 Message-Id: <20260116153051.21678-3-ludwig.rydberg@gaisler.com> X-Mailer: git-send-email 2.35.3 In-Reply-To: <20260116153051.21678-1-ludwig.rydberg@gaisler.com> References: <20260116153051.21678-1-ludwig.rydberg@gaisler.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add support for the clone3 system call to the SPARC architectures. The implementation follows the pattern of the original clone syscall. However, instead of explicitly calling kernel_clone, the clone3 handler calls the generic sys_clone3 handler in kernel/fork. In case no stack is provided, the parents stack is reused. The return call conventions for clone on SPARC are kept for clone3: Parent --> %o0 =3D=3D child's pid, %o1 =3D=3D 0 Child --> %o0 =3D=3D parent's pid, %o1 =3D=3D 1 Closes: https://github.com/sparclinux/issues/issues/10 Signed-off-by: Ludwig Rydberg Tested-by: John Paul Adrian Glaubitz --- arch/sparc/include/asm/syscalls.h | 1 + arch/sparc/include/asm/unistd.h | 2 -- arch/sparc/kernel/entry.S | 15 +++++++++++++++ arch/sparc/kernel/kernel.h | 1 + arch/sparc/kernel/process.c | 25 +++++++++++++++++++++++++ arch/sparc/kernel/process_32.c | 2 +- arch/sparc/kernel/process_64.c | 2 +- arch/sparc/kernel/syscalls.S | 6 ++++++ arch/sparc/kernel/syscalls/syscall.tbl | 2 +- 9 files changed, 51 insertions(+), 5 deletions(-) diff --git a/arch/sparc/include/asm/syscalls.h b/arch/sparc/include/asm/sys= calls.h index 35575fbfb9dc..282e62b66518 100644 --- a/arch/sparc/include/asm/syscalls.h +++ b/arch/sparc/include/asm/syscalls.h @@ -7,5 +7,6 @@ struct pt_regs; asmlinkage long sparc_fork(struct pt_regs *regs); asmlinkage long sparc_vfork(struct pt_regs *regs); asmlinkage long sparc_clone(struct pt_regs *regs); +asmlinkage long sparc_clone3(struct pt_regs *regs); =20 #endif /* _SPARC64_SYSCALLS_H */ diff --git a/arch/sparc/include/asm/unistd.h b/arch/sparc/include/asm/unist= d.h index 3380411a4537..d6bc76706a7a 100644 --- a/arch/sparc/include/asm/unistd.h +++ b/arch/sparc/include/asm/unistd.h @@ -49,8 +49,6 @@ #define __ARCH_WANT_COMPAT_STAT #endif =20 -#define __ARCH_BROKEN_SYS_CLONE3 - #ifdef __32bit_syscall_numbers__ /* Sparc 32-bit only has the "setresuid32", "getresuid32" variants, * it never had the plain ones and there is no value to adding those diff --git a/arch/sparc/kernel/entry.S b/arch/sparc/kernel/entry.S index a3fdee4cd6fa..ea51ef52c952 100644 --- a/arch/sparc/kernel/entry.S +++ b/arch/sparc/kernel/entry.S @@ -907,6 +907,21 @@ flush_patch_four: jmpl %l1 + %lo(sparc_vfork), %g0 add %sp, STACKFRAME_SZ, %o0 =20 + .globl __sys_clone3, flush_patch_five +__sys_clone3: + mov %o7, %l5 +flush_patch_five: + FLUSH_ALL_KERNEL_WINDOWS; + ld [%curptr + TI_TASK], %o4 + rd %psr, %g4 + WRITE_PAUSE + rd %wim, %g5 + WRITE_PAUSE + std %g4, [%o4 + AOFF_task_thread + AOFF_thread_fork_kpsr] + add %sp, STACKFRAME_SZ, %o0 + call sparc_clone3 + mov %l5, %o7 + .align 4 linux_sparc_ni_syscall: sethi %hi(sys_ni_syscall), %l7 diff --git a/arch/sparc/kernel/kernel.h b/arch/sparc/kernel/kernel.h index 8328a3b78a44..4ee85051521a 100644 --- a/arch/sparc/kernel/kernel.h +++ b/arch/sparc/kernel/kernel.h @@ -18,6 +18,7 @@ extern int ncpus_probed; asmlinkage long sparc_clone(struct pt_regs *regs); asmlinkage long sparc_fork(struct pt_regs *regs); asmlinkage long sparc_vfork(struct pt_regs *regs); +asmlinkage long sparc_clone3(struct pt_regs *regs); =20 #ifdef CONFIG_SPARC64 /* setup_64.c */ diff --git a/arch/sparc/kernel/process.c b/arch/sparc/kernel/process.c index 7d69877511fa..b8e23295db69 100644 --- a/arch/sparc/kernel/process.c +++ b/arch/sparc/kernel/process.c @@ -12,6 +12,7 @@ #include #include #include +#include =20 #include "kernel.h" =20 @@ -118,3 +119,27 @@ asmlinkage long sparc_clone(struct pt_regs *regs) =20 return ret; } + +asmlinkage long sparc_clone3(struct pt_regs *regs) +{ + unsigned long sz; + long ret; + struct clone_args __user *cl_args; + + synchronize_user_stack(); + + cl_args =3D (struct clone_args __user *)regs->u_regs[UREG_I0]; + sz =3D regs->u_regs[UREG_I1]; + + ret =3D sys_clone3(cl_args, sz); + + /* If we get an error and potentially restart the system + * call, we're screwed because copy_thread() clobbered + * the parent's %o1. So detect that case and restore it + * here. + */ + if ((unsigned long)ret >=3D -ERESTART_RESTARTBLOCK) + regs->u_regs[UREG_I1] =3D sz; + + return ret; +} diff --git a/arch/sparc/kernel/process_32.c b/arch/sparc/kernel/process_32.c index 5a28c0e91bf1..216c07971c81 100644 --- a/arch/sparc/kernel/process_32.c +++ b/arch/sparc/kernel/process_32.c @@ -261,11 +261,11 @@ extern void ret_from_kernel_thread(void); int copy_thread(struct task_struct *p, const struct kernel_clone_args *arg= s) { u64 clone_flags =3D args->flags; - unsigned long sp =3D args->stack; unsigned long tls =3D args->tls; struct thread_info *ti =3D task_thread_info(p); struct pt_regs *childregs, *regs =3D current_pt_regs(); char *new_stack; + unsigned long sp =3D args->stack ? args->stack : regs->u_regs[UREG_FP]; =20 #ifndef CONFIG_SMP if(last_task_used_math =3D=3D current) { diff --git a/arch/sparc/kernel/process_64.c b/arch/sparc/kernel/process_64.c index 25781923788a..885d617ba29d 100644 --- a/arch/sparc/kernel/process_64.c +++ b/arch/sparc/kernel/process_64.c @@ -568,13 +568,13 @@ void fault_in_user_windows(struct pt_regs *regs) int copy_thread(struct task_struct *p, const struct kernel_clone_args *arg= s) { u64 clone_flags =3D args->flags; - unsigned long sp =3D args->stack; unsigned long tls =3D args->tls; struct thread_info *t =3D task_thread_info(p); struct pt_regs *regs =3D current_pt_regs(); struct sparc_stackf *parent_sf; unsigned long child_stack_sz; char *child_trap_frame; + unsigned long sp =3D args->stack ? args->stack : regs->u_regs[UREG_FP]; =20 /* Calculate offset to stack_frame & pt_regs */ child_stack_sz =3D (STACKFRAME_SZ + TRACEREG_SZ); diff --git a/arch/sparc/kernel/syscalls.S b/arch/sparc/kernel/syscalls.S index 0e8ab0602c36..c8d374a37f98 100644 --- a/arch/sparc/kernel/syscalls.S +++ b/arch/sparc/kernel/syscalls.S @@ -103,6 +103,12 @@ sys_clone: ba,pt %xcc, sparc_clone add %sp, PTREGS_OFF, %o0 =20 + .align 32 +__sys_clone3: + flushw + ba,pt %xcc, sparc_clone3 + add %sp, PTREGS_OFF, %o0 + .globl ret_from_fork ret_from_fork: /* Clear current_thread_info()->new_child. */ diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/sys= calls/syscall.tbl index 39aa26b6a50b..c0307bb09892 100644 --- a/arch/sparc/kernel/syscalls/syscall.tbl +++ b/arch/sparc/kernel/syscalls/syscall.tbl @@ -480,7 +480,7 @@ 432 common fsmount sys_fsmount 433 common fspick sys_fspick 434 common pidfd_open sys_pidfd_open -# 435 reserved for clone3 +435 common clone3 __sys_clone3 436 common close_range sys_close_range 437 common openat2 sys_openat2 438 common pidfd_getfd sys_pidfd_getfd --=20 2.35.3