[PATCH RFC POC 13/50] openrisc: commit fds on syscall exit
From: Christian Brauner <brauner@kernel.org>
Date: 2026-09-15 11:33:00
Also in:
bpf, dri-devel, io-uring, kexec, kvm, linux-alpha, linux-arm-kernel, linux-arm-msm, linux-fsdevel, linux-gpio, linux-hyperv, linux-m68k, linux-mips, linux-mm, linux-sh, linux-um, linuxppc-dev, lkml, sparclinux, virtualization
Subsystem:
openrisc architecture, ptrace support, the rest · Maintainers:
Jonas Bonn, Stefan Kristiansson, Stafford Horne, Oleg Nesterov, Linus Torvalds
Add TIF_FD_SLOTS and test it together with TIF_SYSCALL_TRACE on the way out of a system call. The check used to rely on the flags r30 had been loaded with before the call. Reload them. The syscall may have set the new bit. A task that reserved descriptors calls do_syscall_trace_leave() which commits them before audit and the ptrace exit stop. Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org> --- arch/openrisc/include/asm/thread_info.h | 5 ++++- arch/openrisc/kernel/entry.S | 5 +++-- arch/openrisc/kernel/ptrace.c | 4 ++++ 3 files changed, 11 insertions(+), 3 deletions(-)
diff --git a/arch/openrisc/include/asm/thread_info.h b/arch/openrisc/include/asm/thread_info.h
index e338fff7efb0..3d8a710a809d 100644
--- a/arch/openrisc/include/asm/thread_info.h
+++ b/arch/openrisc/include/asm/thread_info.h@@ -92,6 +92,7 @@ register struct thread_info *current_thread_info_reg asm("r10"); * mode */ #define TIF_NOTIFY_SIGNAL 5 /* signal notifications exist */ +#define TIF_FD_SLOTS 6 /* syscall prepared descriptors */ #define TIF_SYSCALL_TRACEPOINT 8 /* for ftrace syscall instrumentation */ #define TIF_RESTORE_SIGMASK 9 #define TIF_POLLING_NRFLAG 16 /* true if poll_idle() is polling * TIF_NEED_RESCHED
@@ -104,12 +105,14 @@ register struct thread_info *current_thread_info_reg asm("r10"); #define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED) #define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP) #define _TIF_NOTIFY_SIGNAL (1<<TIF_NOTIFY_SIGNAL) +#define _TIF_FD_SLOTS (1<<TIF_FD_SLOTS) #define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG) /* Work to do when returning from interrupt/exception */ /* For OpenRISC, this is anything in the LSW other than syscall trace */ -#define _TIF_WORK_MASK (0xff & ~(_TIF_SYSCALL_TRACE|_TIF_SINGLESTEP)) +#define _TIF_WORK_MASK (0xff & ~(_TIF_SYSCALL_TRACE|_TIF_SINGLESTEP| \ + _TIF_FD_SLOTS)) #endif /* __KERNEL__ */
diff --git a/arch/openrisc/kernel/entry.S b/arch/openrisc/kernel/entry.S
index 18e68680471e..c70265c4fe55 100644
--- a/arch/openrisc/kernel/entry.S
+++ b/arch/openrisc/kernel/entry.S@@ -701,10 +701,11 @@ _syscall_show_regs: #endif _syscall_check_trace_leave: - /* r30 is a callee-saved register so this should still hold the - * _TIF_SYSCALL_TRACE flag from _syscall_check_trace_enter above... + /* Reload the flags, the syscall may have set TIF_FD_SLOTS. * _syscall_trace_leave expects syscall result to be in pt_regs->r11. */ + l.lwz r30,TI_FLAGS(r10) + l.andi r30,r30,(_TIF_SYSCALL_TRACE|_TIF_FD_SLOTS) l.sfne r30,r0 l.bf _syscall_trace_leave l.nop
diff --git a/arch/openrisc/kernel/ptrace.c b/arch/openrisc/kernel/ptrace.c
index 287a9718f0c6..71614b36e516 100644
--- a/arch/openrisc/kernel/ptrace.c
+++ b/arch/openrisc/kernel/ptrace.c@@ -13,6 +13,7 @@ */ #include <linux/kernel.h> +#include <linux/file.h> #include <linux/sched.h> #include <linux/sched/task_stack.h> #include <linux/string.h>
@@ -311,6 +312,9 @@ asmlinkage void do_syscall_trace_leave(struct pt_regs *regs) { int step; + if (test_thread_flag(TIF_FD_SLOTS)) + fd_slots_commit(regs); + audit_syscall_exit(regs); step = test_thread_flag(TIF_SINGLESTEP);
--
2.53.0