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    Subject[PATCH V15 16/24] LoongArch: Add signal handling support
    Date
    Add ucontext/sigcontext definition and signal handling support for
    LoongArch.

    Cc: Eric Biederman <ebiederm@xmission.com>
    Cc: Al Viro <viro@zeniv.linux.org.uk>
    Reviewed-by: WANG Xuerui <git@xen0n.name>
    Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
    Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
    ---
    arch/loongarch/include/uapi/asm/sigcontext.h | 44 ++
    arch/loongarch/include/uapi/asm/signal.h | 13 +
    arch/loongarch/include/uapi/asm/ucontext.h | 35 ++
    arch/loongarch/kernel/signal.c | 566 +++++++++++++++++++
    4 files changed, 658 insertions(+)
    create mode 100644 arch/loongarch/include/uapi/asm/sigcontext.h
    create mode 100644 arch/loongarch/include/uapi/asm/signal.h
    create mode 100644 arch/loongarch/include/uapi/asm/ucontext.h
    create mode 100644 arch/loongarch/kernel/signal.c

    diff --git a/arch/loongarch/include/uapi/asm/sigcontext.h b/arch/loongarch/include/uapi/asm/sigcontext.h
    new file mode 100644
    index 000000000000..52e49b8bf4be
    --- /dev/null
    +++ b/arch/loongarch/include/uapi/asm/sigcontext.h
    @@ -0,0 +1,44 @@
    +/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
    +/*
    + * Author: Hanlu Li <lihanlu@loongson.cn>
    + * Huacai Chen <chenhuacai@loongson.cn>
    + *
    + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
    + */
    +#ifndef _UAPI_ASM_SIGCONTEXT_H
    +#define _UAPI_ASM_SIGCONTEXT_H
    +
    +#include <linux/types.h>
    +#include <linux/posix_types.h>
    +
    +/* FP context was used */
    +#define SC_USED_FP (1 << 0)
    +/* Address error was due to memory load */
    +#define SC_ADDRERR_RD (1 << 30)
    +/* Address error was due to memory store */
    +#define SC_ADDRERR_WR (1 << 31)
    +
    +struct sigcontext {
    + __u64 sc_pc;
    + __u64 sc_regs[32];
    + __u32 sc_flags;
    + __u64 sc_extcontext[0] __attribute__((__aligned__(16)));
    +};
    +
    +#define CONTEXT_INFO_ALIGN 16
    +struct sctx_info {
    + __u32 magic;
    + __u32 size;
    + __u64 padding; /* padding to 16 bytes */
    +};
    +
    +/* FPU context */
    +#define FPU_CTX_MAGIC 0x46505501
    +#define FPU_CTX_ALIGN 8
    +struct fpu_context {
    + __u64 regs[32];
    + __u64 fcc;
    + __u32 fcsr;
    +};
    +
    +#endif /* _UAPI_ASM_SIGCONTEXT_H */
    diff --git a/arch/loongarch/include/uapi/asm/signal.h b/arch/loongarch/include/uapi/asm/signal.h
    new file mode 100644
    index 000000000000..992d965aa13f
    --- /dev/null
    +++ b/arch/loongarch/include/uapi/asm/signal.h
    @@ -0,0 +1,13 @@
    +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
    +/*
    + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
    + */
    +#ifndef _UAPI_ASM_SIGNAL_H
    +#define _UAPI_ASM_SIGNAL_H
    +
    +#define MINSIGSTKSZ 4096
    +#define SIGSTKSZ 16384
    +
    +#include <asm-generic/signal.h>
    +
    +#endif
    diff --git a/arch/loongarch/include/uapi/asm/ucontext.h b/arch/loongarch/include/uapi/asm/ucontext.h
    new file mode 100644
    index 000000000000..12577e22b1c7
    --- /dev/null
    +++ b/arch/loongarch/include/uapi/asm/ucontext.h
    @@ -0,0 +1,35 @@
    +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
    +#ifndef __LOONGARCH_UAPI_ASM_UCONTEXT_H
    +#define __LOONGARCH_UAPI_ASM_UCONTEXT_H
    +
    +/**
    + * struct ucontext - user context structure
    + * @uc_flags:
    + * @uc_link:
    + * @uc_stack:
    + * @uc_mcontext: holds basic processor state
    + * @uc_sigmask:
    + * @uc_extcontext: holds extended processor state
    + */
    +struct ucontext {
    + unsigned long uc_flags;
    + struct ucontext *uc_link;
    + stack_t uc_stack;
    + sigset_t uc_sigmask;
    + /* There's some padding here to allow sigset_t to be expanded in the
    + * future. Though this is unlikely, other architectures put uc_sigmask
    + * at the end of this structure and explicitly state it can be
    + * expanded, so we didn't want to box ourselves in here. */
    + __u8 __unused[1024 / 8 - sizeof(sigset_t)];
    + /* We can't put uc_sigmask at the end of this structure because we need
    + * to be able to expand sigcontext in the future. For example, the
    + * vector ISA extension will almost certainly add ISA state. We want
    + * to ensure all user-visible ISA state can be saved and restored via a
    + * ucontext, so we're putting this at the end in order to allow for
    + * infinite extensibility. Since we know this will be extended and we
    + * assume sigset_t won't be extended an extreme amount, we're
    + * prioritizing this. */
    + struct sigcontext uc_mcontext;
    +};
    +
    +#endif /* __LOONGARCH_UAPI_ASM_UCONTEXT_H */
    diff --git a/arch/loongarch/kernel/signal.c b/arch/loongarch/kernel/signal.c
    new file mode 100644
    index 000000000000..7f4889df4a17
    --- /dev/null
    +++ b/arch/loongarch/kernel/signal.c
    @@ -0,0 +1,566 @@
    +// SPDX-License-Identifier: GPL-2.0+
    +/*
    + * Author: Hanlu Li <lihanlu@loongson.cn>
    + * Huacai Chen <chenhuacai@loongson.cn>
    + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
    + *
    + * Derived from MIPS:
    + * Copyright (C) 1991, 1992 Linus Torvalds
    + * Copyright (C) 1994 - 2000 Ralf Baechle
    + * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
    + * Copyright (C) 2014, Imagination Technologies Ltd.
    + */
    +#include <linux/audit.h>
    +#include <linux/cache.h>
    +#include <linux/context_tracking.h>
    +#include <linux/irqflags.h>
    +#include <linux/sched.h>
    +#include <linux/mm.h>
    +#include <linux/personality.h>
    +#include <linux/smp.h>
    +#include <linux/kernel.h>
    +#include <linux/signal.h>
    +#include <linux/errno.h>
    +#include <linux/wait.h>
    +#include <linux/ptrace.h>
    +#include <linux/unistd.h>
    +#include <linux/compiler.h>
    +#include <linux/syscalls.h>
    +#include <linux/uaccess.h>
    +
    +#include <asm/asm.h>
    +#include <asm/cacheflush.h>
    +#include <asm/cpu-features.h>
    +#include <asm/fpu.h>
    +#include <asm/ucontext.h>
    +#include <asm/vdso.h>
    +
    +#ifdef DEBUG_SIG
    +# define DEBUGP(fmt, args...) printk("%s: " fmt, __func__, ##args)
    +#else
    +# define DEBUGP(fmt, args...)
    +#endif
    +
    +/* Make sure we will not lose FPU ownership */
    +#define lock_fpu_owner() ({ preempt_disable(); pagefault_disable(); })
    +#define unlock_fpu_owner() ({ pagefault_enable(); preempt_enable(); })
    +
    +/* Assembly functions to move context to/from the FPU */
    +extern asmlinkage int
    +_save_fp_context(void __user *fpregs, void __user *fcc, void __user *csr);
    +extern asmlinkage int
    +_restore_fp_context(void __user *fpregs, void __user *fcc, void __user *csr);
    +
    +struct rt_sigframe {
    + struct siginfo rs_info;
    + struct ucontext rs_uctx;
    +};
    +
    +struct _ctx_layout {
    + struct sctx_info *addr;
    + unsigned int size;
    +};
    +
    +struct extctx_layout {
    + unsigned long size;
    + unsigned int flags;
    + struct _ctx_layout fpu;
    + struct _ctx_layout end;
    +};
    +
    +static void __user *get_ctx_through_ctxinfo(struct sctx_info *info)
    +{
    + return (void __user *)((char *)info + sizeof(struct sctx_info));
    +}
    +
    +/*
    + * Thread saved context copy to/from a signal context presumed to be on the
    + * user stack, and therefore accessed with appropriate macros from uaccess.h.
    + */
    +static int copy_fpu_to_sigcontext(struct fpu_context __user *ctx)
    +{
    + int i;
    + int err = 0;
    + uint64_t __user *regs = (uint64_t *)&ctx->regs;
    + uint64_t __user *fcc = &ctx->fcc;
    + uint32_t __user *fcsr = &ctx->fcsr;
    +
    + for (i = 0; i < NUM_FPU_REGS; i++) {
    + err |=
    + __put_user(get_fpr64(&current->thread.fpu.fpr[i], 0),
    + &regs[i]);
    + }
    + err |= __put_user(current->thread.fpu.fcc, fcc);
    + err |= __put_user(current->thread.fpu.fcsr, fcsr);
    +
    + return err;
    +}
    +
    +static int copy_fpu_from_sigcontext(struct fpu_context __user *ctx)
    +{
    + int i;
    + int err = 0;
    + u64 fpr_val;
    + uint64_t __user *regs = (uint64_t *)&ctx->regs;
    + uint64_t __user *fcc = &ctx->fcc;
    + uint32_t __user *fcsr = &ctx->fcsr;
    +
    + for (i = 0; i < NUM_FPU_REGS; i++) {
    + err |= __get_user(fpr_val, &regs[i]);
    + set_fpr64(&current->thread.fpu.fpr[i], 0, fpr_val);
    + }
    + err |= __get_user(current->thread.fpu.fcc, fcc);
    + err |= __get_user(current->thread.fpu.fcsr, fcsr);
    +
    + return err;
    +}
    +
    +/*
    + * Wrappers for the assembly _{save,restore}_fp_context functions.
    + */
    +static int save_hw_fpu_context(struct fpu_context __user *ctx)
    +{
    + uint64_t __user *regs = (uint64_t *)&ctx->regs;
    + uint64_t __user *fcc = &ctx->fcc;
    + uint32_t __user *fcsr = &ctx->fcsr;
    +
    + return _save_fp_context(regs, fcc, fcsr);
    +}
    +
    +static int restore_hw_fpu_context(struct fpu_context __user *ctx)
    +{
    + uint64_t __user *regs = (uint64_t *)&ctx->regs;
    + uint64_t __user *fcc = &ctx->fcc;
    + uint32_t __user *fcsr = &ctx->fcsr;
    +
    + return _restore_fp_context(regs, fcc, fcsr);
    +}
    +
    +static int fcsr_pending(unsigned int __user *fcsr)
    +{
    + int err, sig = 0;
    + unsigned int csr, enabled;
    +
    + err = __get_user(csr, fcsr);
    + enabled = ((csr & FPU_CSR_ALL_E) << 24);
    + /*
    + * If the signal handler set some FPU exceptions, clear it and
    + * send SIGFPE.
    + */
    + if (csr & enabled) {
    + csr &= ~enabled;
    + err |= __put_user(csr, fcsr);
    + sig = SIGFPE;
    + }
    + return err ?: sig;
    +}
    +
    +/*
    + * Helper routines
    + */
    +static int protected_save_fpu_context(struct extctx_layout *extctx)
    +{
    + int err = 0;
    + struct sctx_info __user *info = extctx->fpu.addr;
    + struct fpu_context __user *fpu_ctx = (struct fpu_context *)get_ctx_through_ctxinfo(info);
    + uint64_t __user *regs = (uint64_t *)&fpu_ctx->regs;
    + uint64_t __user *fcc = &fpu_ctx->fcc;
    + uint32_t __user *fcsr = &fpu_ctx->fcsr;
    +
    + while (1) {
    + lock_fpu_owner();
    + if (is_fpu_owner())
    + err = save_hw_fpu_context(fpu_ctx);
    + else
    + err = copy_fpu_to_sigcontext(fpu_ctx);
    + unlock_fpu_owner();
    +
    + err |= __put_user(FPU_CTX_MAGIC, &info->magic);
    + err |= __put_user(extctx->fpu.size, &info->size);
    +
    + if (likely(!err))
    + break;
    + /* Touch the FPU context and try again */
    + err = __put_user(0, &regs[0]) |
    + __put_user(0, &regs[31]) |
    + __put_user(0, fcc) |
    + __put_user(0, fcsr);
    + if (err)
    + return err; /* really bad sigcontext */
    + }
    +
    + return err;
    +}
    +
    +static int protected_restore_fpu_context(struct extctx_layout *extctx)
    +{
    + int err = 0, sig = 0, tmp __maybe_unused;
    + struct sctx_info __user *info = extctx->fpu.addr;
    + struct fpu_context __user *fpu_ctx = (struct fpu_context *)get_ctx_through_ctxinfo(info);
    + uint64_t __user *regs = (uint64_t *)&fpu_ctx->regs;
    + uint64_t __user *fcc = &fpu_ctx->fcc;
    + uint32_t __user *fcsr = &fpu_ctx->fcsr;
    +
    + err = sig = fcsr_pending(fcsr);
    + if (err < 0)
    + return err;
    +
    + while (1) {
    + lock_fpu_owner();
    + if (is_fpu_owner())
    + err = restore_hw_fpu_context(fpu_ctx);
    + else
    + err = copy_fpu_from_sigcontext(fpu_ctx);
    + unlock_fpu_owner();
    +
    + if (likely(!err))
    + break;
    + /* Touch the FPU context and try again */
    + err = __get_user(tmp, &regs[0]) |
    + __get_user(tmp, &regs[31]) |
    + __get_user(tmp, fcc) |
    + __get_user(tmp, fcsr);
    + if (err)
    + break; /* really bad sigcontext */
    + }
    +
    + return err ?: sig;
    +}
    +
    +static int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
    + struct extctx_layout *extctx)
    +{
    + int i, err = 0;
    + struct sctx_info __user *info;
    +
    + err |= __put_user(regs->csr_era, &sc->sc_pc);
    + err |= __put_user(extctx->flags, &sc->sc_flags);
    +
    + err |= __put_user(0, &sc->sc_regs[0]);
    + for (i = 1; i < 32; i++)
    + err |= __put_user(regs->regs[i], &sc->sc_regs[i]);
    +
    + if (extctx->fpu.addr)
    + err |= protected_save_fpu_context(extctx);
    +
    + /* Set the "end" magic */
    + info = (struct sctx_info *)extctx->end.addr;
    + err |= __put_user(0, &info->magic);
    + err |= __put_user(0, &info->size);
    +
    + return err;
    +}
    +
    +static int parse_extcontext(struct sigcontext __user *sc, struct extctx_layout *extctx)
    +{
    + int err = 0;
    + unsigned int magic, size;
    + struct sctx_info __user *info = (struct sctx_info __user *)&sc->sc_extcontext;
    +
    + while(1) {
    + err |= __get_user(magic, &info->magic);
    + err |= __get_user(size, &info->size);
    + if (err)
    + return err;
    +
    + switch (magic) {
    + case 0: /* END */
    + goto done;
    +
    + case FPU_CTX_MAGIC:
    + if (size < (sizeof(struct sctx_info) +
    + sizeof(struct fpu_context)))
    + goto invalid;
    + extctx->fpu.addr = info;
    + break;
    +
    + default:
    + goto invalid;
    + }
    +
    + info = (struct sctx_info *)((char *)info + size);
    + }
    +
    +done:
    + return 0;
    +
    +invalid:
    + return -EINVAL;
    +}
    +
    +static int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
    +{
    + int i, err = 0;
    + struct extctx_layout extctx;
    +
    + memset(&extctx, 0, sizeof(struct extctx_layout));
    +
    + err = __get_user(extctx.flags, &sc->sc_flags);
    + if (err)
    + goto bad;
    +
    + err = parse_extcontext(sc, &extctx);
    + if (err)
    + goto bad;
    +
    + conditional_used_math(extctx.flags & SC_USED_FP);
    +
    + /*
    + * The signal handler may have used FPU; give it up if the program
    + * doesn't want it following sigreturn.
    + */
    + if (!(extctx.flags & SC_USED_FP))
    + lose_fpu(0);
    +
    + /* Always make any pending restarted system calls return -EINTR */
    + current->restart_block.fn = do_no_restart_syscall;
    +
    + err |= __get_user(regs->csr_era, &sc->sc_pc);
    + for (i = 1; i < 32; i++)
    + err |= __get_user(regs->regs[i], &sc->sc_regs[i]);
    +
    + if (extctx.fpu.addr)
    + err |= protected_restore_fpu_context(&extctx);
    +
    +bad:
    + return err;
    +}
    +
    +static unsigned int handle_flags(void)
    +{
    + unsigned int flags = 0;
    +
    + flags = used_math() ? SC_USED_FP : 0;
    +
    + switch (current->thread.error_code) {
    + case 1:
    + flags |= SC_ADDRERR_RD;
    + break;
    + case 2:
    + flags |= SC_ADDRERR_WR;
    + break;
    + }
    +
    + return flags;
    +}
    +
    +static unsigned long extframe_alloc(struct extctx_layout *extctx,
    + struct _ctx_layout *layout,
    + size_t size, unsigned int align, unsigned long base)
    +{
    + unsigned long new_base = base - size;
    +
    + new_base = round_down(new_base, (align < 16 ? 16 : align));
    + new_base -= sizeof(struct sctx_info);
    +
    + layout->addr = (void *)new_base;
    + layout->size = (unsigned int)(base - new_base);
    + extctx->size += layout->size;
    +
    + return new_base;
    +}
    +
    +static unsigned long setup_extcontext(struct extctx_layout *extctx, unsigned long sp)
    +{
    + unsigned long new_sp = sp;
    +
    + memset(extctx, 0, sizeof(struct extctx_layout));
    +
    + extctx->flags = handle_flags();
    +
    + /* Grow down, alloc "end" context info first. */
    + new_sp -= sizeof(struct sctx_info);
    + extctx->end.addr = (void *)new_sp;
    + extctx->end.size = (unsigned int)sizeof(struct sctx_info);
    + extctx->size += extctx->end.size;
    +
    + if (extctx->flags & SC_USED_FP) {
    + if (cpu_has_fpu)
    + new_sp = extframe_alloc(extctx, &extctx->fpu,
    + sizeof(struct fpu_context), FPU_CTX_ALIGN, new_sp);
    + }
    +
    + return new_sp;
    +}
    +
    +void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs,
    + struct extctx_layout *extctx)
    +{
    + unsigned long sp;
    +
    + /* Default to using normal stack */
    + sp = regs->regs[3];
    +
    + /*
    + * If we are on the alternate signal stack and would overflow it, don't.
    + * Return an always-bogus address instead so we will die with SIGSEGV.
    + */
    + if (on_sig_stack(sp) &&
    + !likely(on_sig_stack(sp - sizeof(struct rt_sigframe))))
    + return (void __user __force *)(-1UL);
    +
    + sp = sigsp(sp, ksig);
    + sp = round_down(sp, 16);
    + sp = setup_extcontext(extctx, sp);
    + sp -= sizeof(struct rt_sigframe);
    +
    + if (!IS_ALIGNED(sp, 16))
    + BUG();
    +
    + return (void __user *)sp;
    +}
    +
    +/*
    + * Atomically swap in the new signal mask, and wait for a signal.
    + */
    +
    +asmlinkage long sys_rt_sigreturn(void)
    +{
    + int sig;
    + sigset_t set;
    + struct pt_regs *regs;
    + struct rt_sigframe __user *frame;
    +
    + regs = current_pt_regs();
    + frame = (struct rt_sigframe __user *)regs->regs[3];
    + if (!access_ok(frame, sizeof(*frame)))
    + goto badframe;
    + if (__copy_from_user(&set, &frame->rs_uctx.uc_sigmask, sizeof(set)))
    + goto badframe;
    +
    + set_current_blocked(&set);
    +
    + sig = restore_sigcontext(regs, &frame->rs_uctx.uc_mcontext);
    + if (sig < 0)
    + goto badframe;
    + else if (sig)
    + force_sig(sig);
    +
    + regs->regs[0] = 0; /* No syscall restarting */
    + if (restore_altstack(&frame->rs_uctx.uc_stack))
    + goto badframe;
    +
    + return regs->regs[4];
    +
    +badframe:
    + force_sig(SIGSEGV);
    + return 0;
    +}
    +
    +static int setup_rt_frame(void *sig_return, struct ksignal *ksig,
    + struct pt_regs *regs, sigset_t *set)
    +{
    + int err = 0;
    + struct extctx_layout extctx;
    + struct rt_sigframe __user *frame;
    +
    + frame = get_sigframe(ksig, regs, &extctx);
    + if (!access_ok(frame, sizeof(*frame) + extctx.size))
    + return -EFAULT;
    +
    + /* Create siginfo. */
    + err |= copy_siginfo_to_user(&frame->rs_info, &ksig->info);
    +
    + /* Create the ucontext. */
    + err |= __put_user(0, &frame->rs_uctx.uc_flags);
    + err |= __put_user(NULL, &frame->rs_uctx.uc_link);
    + err |= __save_altstack(&frame->rs_uctx.uc_stack, regs->regs[3]);
    + err |= setup_sigcontext(regs, &frame->rs_uctx.uc_mcontext, &extctx);
    + err |= __copy_to_user(&frame->rs_uctx.uc_sigmask, set, sizeof(*set));
    +
    + if (err)
    + return -EFAULT;
    +
    + /*
    + * Arguments to signal handler:
    + *
    + * a0 = signal number
    + * a1 = pointer to siginfo
    + * a2 = pointer to ucontext
    + *
    + * c0_era point to the signal handler, $r3 (sp) points to
    + * the struct rt_sigframe.
    + */
    + regs->regs[4] = ksig->sig;
    + regs->regs[5] = (unsigned long) &frame->rs_info;
    + regs->regs[6] = (unsigned long) &frame->rs_uctx;
    + regs->regs[3] = (unsigned long) frame;
    + regs->regs[1] = (unsigned long) sig_return;
    + regs->csr_era = (unsigned long) ksig->ka.sa.sa_handler;
    +
    + DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
    + current->comm, current->pid,
    + frame, regs->csr_era, regs->regs[1]);
    +
    + return 0;
    +}
    +
    +static void handle_signal(struct ksignal *ksig, struct pt_regs *regs)
    +{
    + int ret;
    + sigset_t *oldset = sigmask_to_save();
    + void *vdso = current->mm->context.vdso;
    +
    + /* Are we from a system call? */
    + if (regs->regs[0]) {
    + switch (regs->regs[4]) {
    + case -ERESTART_RESTARTBLOCK:
    + case -ERESTARTNOHAND:
    + regs->regs[4] = -EINTR;
    + break;
    + case -ERESTARTSYS:
    + if (!(ksig->ka.sa.sa_flags & SA_RESTART)) {
    + regs->regs[4] = -EINTR;
    + break;
    + }
    + fallthrough;
    + case -ERESTARTNOINTR:
    + regs->regs[4] = regs->orig_a0;
    + regs->csr_era -= 4;
    + }
    +
    + regs->regs[0] = 0; /* Don't deal with this again. */
    + }
    +
    + rseq_signal_deliver(ksig, regs);
    +
    + ret = setup_rt_frame(vdso + current->thread.vdso->offset_sigreturn, ksig, regs, oldset);
    +
    + signal_setup_done(ret, ksig, 0);
    +}
    +
    +void arch_do_signal_or_restart(struct pt_regs *regs, bool has_signal)
    +{
    + struct ksignal ksig;
    +
    + if (has_signal && get_signal(&ksig)) {
    + /* Whee! Actually deliver the signal. */
    + handle_signal(&ksig, regs);
    + return;
    + }
    +
    + /* Are we from a system call? */
    + if (regs->regs[0]) {
    + switch (regs->regs[4]) {
    + case -ERESTARTNOHAND:
    + case -ERESTARTSYS:
    + case -ERESTARTNOINTR:
    + regs->regs[4] = regs->orig_a0;
    + regs->csr_era -= 4;
    + break;
    +
    + case -ERESTART_RESTARTBLOCK:
    + regs->regs[4] = regs->orig_a0;
    + regs->regs[11] = __NR_restart_syscall;
    + regs->csr_era -= 4;
    + break;
    + }
    + regs->regs[0] = 0; /* Don't deal with this again. */
    + }
    +
    + /*
    + * If there's no signal to deliver, we just put the saved sigmask
    + * back
    + */
    + restore_saved_sigmask();
    +}
    --
    2.27.0
    \
     
     \ /
      Last update: 2022-06-03 09:29    [W:2.643 / U:0.144 seconds]
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