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https://github.com/AuxXxilium/linux_dsm_epyc7002.git
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22a8cdd603
Mike Frysinger pointed out that calling tracehook_signal_handler with stepping=0 missed testing the thread flags, resulting in not calling ptrace_notify. Fix this by testing if we're single stepping or branch stepping and setting the flag accordingly. Tested, seems to work. Reported-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
661 lines
19 KiB
C
661 lines
19 KiB
C
/*
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* linux/arch/parisc/kernel/signal.c: Architecture-specific signal
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* handling support.
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*
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* Copyright (C) 2000 David Huggins-Daines <dhd@debian.org>
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* Copyright (C) 2000 Linuxcare, Inc.
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*
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* Based on the ia64, i386, and alpha versions.
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*
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* Like the IA-64, we are a recent enough port (we are *starting*
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* with glibc2.2) that we do not need to support the old non-realtime
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* Linux signals. Therefore we don't. HP/UX signals will go in
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* arch/parisc/hpux/signal.c when we figure out how to do them.
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*/
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#include <linux/sched.h>
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#include <linux/mm.h>
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#include <linux/smp.h>
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#include <linux/kernel.h>
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#include <linux/signal.h>
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#include <linux/errno.h>
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#include <linux/wait.h>
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#include <linux/ptrace.h>
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#include <linux/tracehook.h>
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#include <linux/unistd.h>
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#include <linux/stddef.h>
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#include <linux/compat.h>
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#include <linux/elf.h>
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#include <asm/ucontext.h>
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#include <asm/rt_sigframe.h>
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#include <asm/uaccess.h>
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#include <asm/pgalloc.h>
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#include <asm/cacheflush.h>
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#include <asm/asm-offsets.h>
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#ifdef CONFIG_COMPAT
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#include "signal32.h"
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#endif
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#define DEBUG_SIG 0
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#define DEBUG_SIG_LEVEL 2
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#if DEBUG_SIG
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#define DBG(LEVEL, ...) \
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((DEBUG_SIG_LEVEL >= LEVEL) \
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? printk(__VA_ARGS__) : (void) 0)
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#else
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#define DBG(LEVEL, ...)
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#endif
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#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
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/* gcc will complain if a pointer is cast to an integer of different
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* size. If you really need to do this (and we do for an ELF32 user
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* application in an ELF64 kernel) then you have to do a cast to an
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* integer of the same size first. The A() macro accomplishes
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* this. */
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#define A(__x) ((unsigned long)(__x))
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/*
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* Atomically swap in the new signal mask, and wait for a signal.
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*/
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#ifdef CONFIG_64BIT
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#include "sys32.h"
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#endif
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/*
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* Do a signal return - restore sigcontext.
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*/
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/* Trampoline for calling rt_sigreturn() */
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#define INSN_LDI_R25_0 0x34190000 /* ldi 0,%r25 (in_syscall=0) */
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#define INSN_LDI_R25_1 0x34190002 /* ldi 1,%r25 (in_syscall=1) */
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#define INSN_LDI_R20 0x3414015a /* ldi __NR_rt_sigreturn,%r20 */
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#define INSN_BLE_SR2_R0 0xe4008200 /* be,l 0x100(%sr2,%r0),%sr0,%r31 */
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#define INSN_NOP 0x08000240 /* nop */
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/* For debugging */
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#define INSN_DIE_HORRIBLY 0x68000ccc /* stw %r0,0x666(%sr0,%r0) */
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static long
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restore_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs)
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{
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long err = 0;
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err |= __copy_from_user(regs->gr, sc->sc_gr, sizeof(regs->gr));
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err |= __copy_from_user(regs->fr, sc->sc_fr, sizeof(regs->fr));
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err |= __copy_from_user(regs->iaoq, sc->sc_iaoq, sizeof(regs->iaoq));
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err |= __copy_from_user(regs->iasq, sc->sc_iasq, sizeof(regs->iasq));
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err |= __get_user(regs->sar, &sc->sc_sar);
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DBG(2,"restore_sigcontext: iaoq is 0x%#lx / 0x%#lx\n",
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regs->iaoq[0],regs->iaoq[1]);
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DBG(2,"restore_sigcontext: r28 is %ld\n", regs->gr[28]);
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return err;
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}
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void
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sys_rt_sigreturn(struct pt_regs *regs, int in_syscall)
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{
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struct rt_sigframe __user *frame;
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struct siginfo si;
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sigset_t set;
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unsigned long usp = (regs->gr[30] & ~(0x01UL));
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unsigned long sigframe_size = PARISC_RT_SIGFRAME_SIZE;
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#ifdef CONFIG_64BIT
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compat_sigset_t compat_set;
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struct compat_rt_sigframe __user * compat_frame;
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if (is_compat_task())
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sigframe_size = PARISC_RT_SIGFRAME_SIZE32;
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#endif
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/* Unwind the user stack to get the rt_sigframe structure. */
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frame = (struct rt_sigframe __user *)
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(usp - sigframe_size);
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DBG(2,"sys_rt_sigreturn: frame is %p\n", frame);
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#ifdef CONFIG_64BIT
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compat_frame = (struct compat_rt_sigframe __user *)frame;
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if (is_compat_task()) {
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DBG(2,"sys_rt_sigreturn: ELF32 process.\n");
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if (__copy_from_user(&compat_set, &compat_frame->uc.uc_sigmask, sizeof(compat_set)))
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goto give_sigsegv;
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sigset_32to64(&set,&compat_set);
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} else
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#endif
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{
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if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
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goto give_sigsegv;
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}
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sigdelsetmask(&set, ~_BLOCKABLE);
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spin_lock_irq(¤t->sighand->siglock);
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current->blocked = set;
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recalc_sigpending();
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spin_unlock_irq(¤t->sighand->siglock);
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/* Good thing we saved the old gr[30], eh? */
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#ifdef CONFIG_64BIT
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if (is_compat_task()) {
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DBG(1,"sys_rt_sigreturn: compat_frame->uc.uc_mcontext 0x%p\n",
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&compat_frame->uc.uc_mcontext);
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// FIXME: Load upper half from register file
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if (restore_sigcontext32(&compat_frame->uc.uc_mcontext,
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&compat_frame->regs, regs))
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goto give_sigsegv;
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DBG(1,"sys_rt_sigreturn: usp %#08lx stack 0x%p\n",
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usp, &compat_frame->uc.uc_stack);
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if (do_sigaltstack32(&compat_frame->uc.uc_stack, NULL, usp) == -EFAULT)
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goto give_sigsegv;
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} else
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#endif
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{
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DBG(1,"sys_rt_sigreturn: frame->uc.uc_mcontext 0x%p\n",
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&frame->uc.uc_mcontext);
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if (restore_sigcontext(&frame->uc.uc_mcontext, regs))
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goto give_sigsegv;
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DBG(1,"sys_rt_sigreturn: usp %#08lx stack 0x%p\n",
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usp, &frame->uc.uc_stack);
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if (do_sigaltstack(&frame->uc.uc_stack, NULL, usp) == -EFAULT)
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goto give_sigsegv;
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}
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/* If we are on the syscall path IAOQ will not be restored, and
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* if we are on the interrupt path we must not corrupt gr31.
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*/
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if (in_syscall)
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regs->gr[31] = regs->iaoq[0];
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#if DEBUG_SIG
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DBG(1,"sys_rt_sigreturn: returning to %#lx, DUMPING REGS:\n", regs->iaoq[0]);
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show_regs(regs);
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#endif
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return;
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give_sigsegv:
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DBG(1,"sys_rt_sigreturn: Sending SIGSEGV\n");
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si.si_signo = SIGSEGV;
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si.si_errno = 0;
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si.si_code = SI_KERNEL;
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si.si_pid = task_pid_vnr(current);
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si.si_uid = current_uid();
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si.si_addr = &frame->uc;
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force_sig_info(SIGSEGV, &si, current);
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return;
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}
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/*
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* Set up a signal frame.
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*/
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static inline void __user *
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get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
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{
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/*FIXME: ELF32 vs. ELF64 has different frame_size, but since we
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don't use the parameter it doesn't matter */
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DBG(1,"get_sigframe: ka = %#lx, sp = %#lx, frame_size = %#lx\n",
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(unsigned long)ka, sp, frame_size);
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if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp))
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sp = current->sas_ss_sp; /* Stacks grow up! */
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DBG(1,"get_sigframe: Returning sp = %#lx\n", (unsigned long)sp);
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return (void __user *) sp; /* Stacks grow up. Fun. */
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}
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static long
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setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, int in_syscall)
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{
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unsigned long flags = 0;
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long err = 0;
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if (on_sig_stack((unsigned long) sc))
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flags |= PARISC_SC_FLAG_ONSTACK;
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if (in_syscall) {
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flags |= PARISC_SC_FLAG_IN_SYSCALL;
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/* regs->iaoq is undefined in the syscall return path */
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err |= __put_user(regs->gr[31], &sc->sc_iaoq[0]);
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err |= __put_user(regs->gr[31]+4, &sc->sc_iaoq[1]);
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err |= __put_user(regs->sr[3], &sc->sc_iasq[0]);
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err |= __put_user(regs->sr[3], &sc->sc_iasq[1]);
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DBG(1,"setup_sigcontext: iaoq %#lx / %#lx (in syscall)\n",
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regs->gr[31], regs->gr[31]+4);
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} else {
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err |= __copy_to_user(sc->sc_iaoq, regs->iaoq, sizeof(regs->iaoq));
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err |= __copy_to_user(sc->sc_iasq, regs->iasq, sizeof(regs->iasq));
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DBG(1,"setup_sigcontext: iaoq %#lx / %#lx (not in syscall)\n",
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regs->iaoq[0], regs->iaoq[1]);
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}
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err |= __put_user(flags, &sc->sc_flags);
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err |= __copy_to_user(sc->sc_gr, regs->gr, sizeof(regs->gr));
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err |= __copy_to_user(sc->sc_fr, regs->fr, sizeof(regs->fr));
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err |= __put_user(regs->sar, &sc->sc_sar);
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DBG(1,"setup_sigcontext: r28 is %ld\n", regs->gr[28]);
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return err;
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}
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static long
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setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
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sigset_t *set, struct pt_regs *regs, int in_syscall)
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{
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struct rt_sigframe __user *frame;
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unsigned long rp, usp;
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unsigned long haddr, sigframe_size;
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int err = 0;
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#ifdef CONFIG_64BIT
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compat_int_t compat_val;
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struct compat_rt_sigframe __user * compat_frame;
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compat_sigset_t compat_set;
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#endif
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usp = (regs->gr[30] & ~(0x01UL));
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/*FIXME: frame_size parameter is unused, remove it. */
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frame = get_sigframe(ka, usp, sizeof(*frame));
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DBG(1,"SETUP_RT_FRAME: START\n");
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DBG(1,"setup_rt_frame: frame %p info %p\n", frame, info);
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#ifdef CONFIG_64BIT
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compat_frame = (struct compat_rt_sigframe __user *)frame;
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if (is_compat_task()) {
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DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &compat_frame->info);
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err |= copy_siginfo_to_user32(&compat_frame->info, info);
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DBG(1,"SETUP_RT_FRAME: 1\n");
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compat_val = (compat_int_t)current->sas_ss_sp;
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err |= __put_user(compat_val, &compat_frame->uc.uc_stack.ss_sp);
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DBG(1,"SETUP_RT_FRAME: 2\n");
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compat_val = (compat_int_t)current->sas_ss_size;
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err |= __put_user(compat_val, &compat_frame->uc.uc_stack.ss_size);
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DBG(1,"SETUP_RT_FRAME: 3\n");
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compat_val = sas_ss_flags(regs->gr[30]);
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err |= __put_user(compat_val, &compat_frame->uc.uc_stack.ss_flags);
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DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &compat_frame->uc);
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DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &compat_frame->uc.uc_mcontext);
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err |= setup_sigcontext32(&compat_frame->uc.uc_mcontext,
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&compat_frame->regs, regs, in_syscall);
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sigset_64to32(&compat_set,set);
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err |= __copy_to_user(&compat_frame->uc.uc_sigmask, &compat_set, sizeof(compat_set));
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} else
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#endif
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{
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DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &frame->info);
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err |= copy_siginfo_to_user(&frame->info, info);
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err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
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err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
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err |= __put_user(sas_ss_flags(regs->gr[30]),
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&frame->uc.uc_stack.ss_flags);
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DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &frame->uc);
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DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &frame->uc.uc_mcontext);
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err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, in_syscall);
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/* FIXME: Should probably be converted aswell for the compat case */
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err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
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}
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if (err)
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goto give_sigsegv;
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/* Set up to return from userspace. If provided, use a stub
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already in userspace. The first words of tramp are used to
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save the previous sigrestartblock trampoline that might be
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on the stack. We start the sigreturn trampoline at
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SIGRESTARTBLOCK_TRAMP+X. */
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err |= __put_user(in_syscall ? INSN_LDI_R25_1 : INSN_LDI_R25_0,
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&frame->tramp[SIGRESTARTBLOCK_TRAMP+0]);
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err |= __put_user(INSN_LDI_R20,
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&frame->tramp[SIGRESTARTBLOCK_TRAMP+1]);
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err |= __put_user(INSN_BLE_SR2_R0,
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&frame->tramp[SIGRESTARTBLOCK_TRAMP+2]);
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err |= __put_user(INSN_NOP, &frame->tramp[SIGRESTARTBLOCK_TRAMP+3]);
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#if DEBUG_SIG
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/* Assert that we're flushing in the correct space... */
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{
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int sid;
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asm ("mfsp %%sr3,%0" : "=r" (sid));
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DBG(1,"setup_rt_frame: Flushing 64 bytes at space %#x offset %p\n",
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sid, frame->tramp);
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}
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#endif
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flush_user_dcache_range((unsigned long) &frame->tramp[0],
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(unsigned long) &frame->tramp[TRAMP_SIZE]);
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flush_user_icache_range((unsigned long) &frame->tramp[0],
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(unsigned long) &frame->tramp[TRAMP_SIZE]);
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/* TRAMP Words 0-4, Length 5 = SIGRESTARTBLOCK_TRAMP
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* TRAMP Words 5-9, Length 4 = SIGRETURN_TRAMP
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* So the SIGRETURN_TRAMP is at the end of SIGRESTARTBLOCK_TRAMP
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*/
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rp = (unsigned long) &frame->tramp[SIGRESTARTBLOCK_TRAMP];
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if (err)
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goto give_sigsegv;
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haddr = A(ka->sa.sa_handler);
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/* The sa_handler may be a pointer to a function descriptor */
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#ifdef CONFIG_64BIT
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if (is_compat_task()) {
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#endif
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if (haddr & PA_PLABEL_FDESC) {
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Elf32_Fdesc fdesc;
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Elf32_Fdesc __user *ufdesc = (Elf32_Fdesc __user *)A(haddr & ~3);
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err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc));
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if (err)
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goto give_sigsegv;
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haddr = fdesc.addr;
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regs->gr[19] = fdesc.gp;
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}
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#ifdef CONFIG_64BIT
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} else {
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Elf64_Fdesc fdesc;
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Elf64_Fdesc __user *ufdesc = (Elf64_Fdesc __user *)A(haddr & ~3);
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err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc));
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if (err)
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goto give_sigsegv;
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haddr = fdesc.addr;
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regs->gr[19] = fdesc.gp;
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DBG(1,"setup_rt_frame: 64 bit signal, exe=%#lx, r19=%#lx, in_syscall=%d\n",
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haddr, regs->gr[19], in_syscall);
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}
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#endif
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/* The syscall return path will create IAOQ values from r31.
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*/
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sigframe_size = PARISC_RT_SIGFRAME_SIZE;
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#ifdef CONFIG_64BIT
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if (is_compat_task())
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sigframe_size = PARISC_RT_SIGFRAME_SIZE32;
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#endif
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if (in_syscall) {
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regs->gr[31] = haddr;
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#ifdef CONFIG_64BIT
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if (!test_thread_flag(TIF_32BIT))
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sigframe_size |= 1;
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#endif
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} else {
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unsigned long psw = USER_PSW;
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#ifdef CONFIG_64BIT
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if (!test_thread_flag(TIF_32BIT))
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psw |= PSW_W;
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#endif
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/* If we are singlestepping, arrange a trap to be delivered
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when we return to userspace. Note the semantics -- we
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should trap before the first insn in the handler is
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executed. Ref:
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http://sources.redhat.com/ml/gdb/2004-11/msg00245.html
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*/
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if (pa_psw(current)->r) {
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pa_psw(current)->r = 0;
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psw |= PSW_R;
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mtctl(-1, 0);
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}
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regs->gr[0] = psw;
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regs->iaoq[0] = haddr | 3;
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regs->iaoq[1] = regs->iaoq[0] + 4;
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}
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regs->gr[2] = rp; /* userland return pointer */
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regs->gr[26] = sig; /* signal number */
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#ifdef CONFIG_64BIT
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if (is_compat_task()) {
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regs->gr[25] = A(&compat_frame->info); /* siginfo pointer */
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regs->gr[24] = A(&compat_frame->uc); /* ucontext pointer */
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} else
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#endif
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{
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regs->gr[25] = A(&frame->info); /* siginfo pointer */
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regs->gr[24] = A(&frame->uc); /* ucontext pointer */
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}
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DBG(1,"setup_rt_frame: making sigreturn frame: %#lx + %#lx = %#lx\n",
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regs->gr[30], sigframe_size,
|
|
regs->gr[30] + sigframe_size);
|
|
/* Raise the user stack pointer to make a proper call frame. */
|
|
regs->gr[30] = (A(frame) + sigframe_size);
|
|
|
|
|
|
DBG(1,"setup_rt_frame: sig deliver (%s,%d) frame=0x%p sp=%#lx iaoq=%#lx/%#lx rp=%#lx\n",
|
|
current->comm, current->pid, frame, regs->gr[30],
|
|
regs->iaoq[0], regs->iaoq[1], rp);
|
|
|
|
return 1;
|
|
|
|
give_sigsegv:
|
|
DBG(1,"setup_rt_frame: sending SIGSEGV\n");
|
|
force_sigsegv(sig, current);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* OK, we're invoking a handler.
|
|
*/
|
|
|
|
static long
|
|
handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
|
|
sigset_t *oldset, struct pt_regs *regs, int in_syscall)
|
|
{
|
|
DBG(1,"handle_signal: sig=%ld, ka=%p, info=%p, oldset=%p, regs=%p\n",
|
|
sig, ka, info, oldset, regs);
|
|
|
|
/* Set up the stack frame */
|
|
if (!setup_rt_frame(sig, ka, info, oldset, regs, in_syscall))
|
|
return 0;
|
|
|
|
spin_lock_irq(¤t->sighand->siglock);
|
|
sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask);
|
|
if (!(ka->sa.sa_flags & SA_NODEFER))
|
|
sigaddset(¤t->blocked,sig);
|
|
recalc_sigpending();
|
|
spin_unlock_irq(¤t->sighand->siglock);
|
|
|
|
tracehook_signal_handler(sig, info, ka, regs,
|
|
test_thread_flag(TIF_SINGLESTEP) ||
|
|
test_thread_flag(TIF_BLOCKSTEP));
|
|
|
|
return 1;
|
|
}
|
|
|
|
static inline void
|
|
syscall_restart(struct pt_regs *regs, struct k_sigaction *ka)
|
|
{
|
|
/* Check the return code */
|
|
switch (regs->gr[28]) {
|
|
case -ERESTART_RESTARTBLOCK:
|
|
current_thread_info()->restart_block.fn =
|
|
do_no_restart_syscall;
|
|
case -ERESTARTNOHAND:
|
|
DBG(1,"ERESTARTNOHAND: returning -EINTR\n");
|
|
regs->gr[28] = -EINTR;
|
|
break;
|
|
|
|
case -ERESTARTSYS:
|
|
if (!(ka->sa.sa_flags & SA_RESTART)) {
|
|
DBG(1,"ERESTARTSYS: putting -EINTR\n");
|
|
regs->gr[28] = -EINTR;
|
|
break;
|
|
}
|
|
/* fallthrough */
|
|
case -ERESTARTNOINTR:
|
|
/* A syscall is just a branch, so all
|
|
* we have to do is fiddle the return pointer.
|
|
*/
|
|
regs->gr[31] -= 8; /* delayed branching */
|
|
/* Preserve original r28. */
|
|
regs->gr[28] = regs->orig_r28;
|
|
break;
|
|
}
|
|
}
|
|
|
|
static inline void
|
|
insert_restart_trampoline(struct pt_regs *regs)
|
|
{
|
|
switch(regs->gr[28]) {
|
|
case -ERESTART_RESTARTBLOCK: {
|
|
/* Restart the system call - no handlers present */
|
|
unsigned int *usp = (unsigned int *)regs->gr[30];
|
|
|
|
/* Setup a trampoline to restart the syscall
|
|
* with __NR_restart_syscall
|
|
*
|
|
* 0: <return address (orig r31)>
|
|
* 4: <2nd half for 64-bit>
|
|
* 8: ldw 0(%sp), %r31
|
|
* 12: be 0x100(%sr2, %r0)
|
|
* 16: ldi __NR_restart_syscall, %r20
|
|
*/
|
|
#ifdef CONFIG_64BIT
|
|
put_user(regs->gr[31] >> 32, &usp[0]);
|
|
put_user(regs->gr[31] & 0xffffffff, &usp[1]);
|
|
put_user(0x0fc010df, &usp[2]);
|
|
#else
|
|
put_user(regs->gr[31], &usp[0]);
|
|
put_user(0x0fc0109f, &usp[2]);
|
|
#endif
|
|
put_user(0xe0008200, &usp[3]);
|
|
put_user(0x34140000, &usp[4]);
|
|
|
|
/* Stack is 64-byte aligned, and we only need
|
|
* to flush 1 cache line.
|
|
* Flushing one cacheline is cheap.
|
|
* "sync" on bigger (> 4 way) boxes is not.
|
|
*/
|
|
flush_user_dcache_range(regs->gr[30], regs->gr[30] + 4);
|
|
flush_user_icache_range(regs->gr[30], regs->gr[30] + 4);
|
|
|
|
regs->gr[31] = regs->gr[30] + 8;
|
|
/* Preserve original r28. */
|
|
regs->gr[28] = regs->orig_r28;
|
|
|
|
return;
|
|
}
|
|
case -ERESTARTNOHAND:
|
|
case -ERESTARTSYS:
|
|
case -ERESTARTNOINTR: {
|
|
/* Hooray for delayed branching. We don't
|
|
* have to restore %r20 (the system call
|
|
* number) because it gets loaded in the delay
|
|
* slot of the branch external instruction.
|
|
*/
|
|
regs->gr[31] -= 8;
|
|
/* Preserve original r28. */
|
|
regs->gr[28] = regs->orig_r28;
|
|
|
|
return;
|
|
}
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Note that 'init' is a special process: it doesn't get signals it doesn't
|
|
* want to handle. Thus you cannot kill init even with a SIGKILL even by
|
|
* mistake.
|
|
*
|
|
* We need to be able to restore the syscall arguments (r21-r26) to
|
|
* restart syscalls. Thus, the syscall path should save them in the
|
|
* pt_regs structure (it's okay to do so since they are caller-save
|
|
* registers). As noted below, the syscall number gets restored for
|
|
* us due to the magic of delayed branching.
|
|
*/
|
|
asmlinkage void
|
|
do_signal(struct pt_regs *regs, long in_syscall)
|
|
{
|
|
siginfo_t info;
|
|
struct k_sigaction ka;
|
|
int signr;
|
|
sigset_t *oldset;
|
|
|
|
DBG(1,"\ndo_signal: oldset=0x%p, regs=0x%p, sr7 %#lx, in_syscall=%d\n",
|
|
oldset, regs, regs->sr[7], in_syscall);
|
|
|
|
/* Everyone else checks to see if they are in kernel mode at
|
|
this point and exits if that's the case. I'm not sure why
|
|
we would be called in that case, but for some reason we
|
|
are. */
|
|
|
|
if (test_thread_flag(TIF_RESTORE_SIGMASK))
|
|
oldset = ¤t->saved_sigmask;
|
|
else
|
|
oldset = ¤t->blocked;
|
|
|
|
DBG(1,"do_signal: oldset %08lx / %08lx\n",
|
|
oldset->sig[0], oldset->sig[1]);
|
|
|
|
|
|
/* May need to force signal if handle_signal failed to deliver */
|
|
while (1) {
|
|
|
|
signr = get_signal_to_deliver(&info, &ka, regs, NULL);
|
|
DBG(3,"do_signal: signr = %d, regs->gr[28] = %ld\n", signr, regs->gr[28]);
|
|
|
|
if (signr <= 0)
|
|
break;
|
|
|
|
/* Restart a system call if necessary. */
|
|
if (in_syscall)
|
|
syscall_restart(regs, &ka);
|
|
|
|
/* Whee! Actually deliver the signal. If the
|
|
delivery failed, we need to continue to iterate in
|
|
this loop so we can deliver the SIGSEGV... */
|
|
if (handle_signal(signr, &info, &ka, oldset,
|
|
regs, in_syscall)) {
|
|
DBG(1,KERN_DEBUG "do_signal: Exit (success), regs->gr[28] = %ld\n",
|
|
regs->gr[28]);
|
|
if (test_thread_flag(TIF_RESTORE_SIGMASK))
|
|
clear_thread_flag(TIF_RESTORE_SIGMASK);
|
|
return;
|
|
}
|
|
}
|
|
/* end of while(1) looping forever if we can't force a signal */
|
|
|
|
/* Did we come from a system call? */
|
|
if (in_syscall)
|
|
insert_restart_trampoline(regs);
|
|
|
|
DBG(1,"do_signal: Exit (not delivered), regs->gr[28] = %ld\n",
|
|
regs->gr[28]);
|
|
|
|
if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
|
|
clear_thread_flag(TIF_RESTORE_SIGMASK);
|
|
sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL);
|
|
}
|
|
|
|
return;
|
|
}
|
|
|
|
void do_notify_resume(struct pt_regs *regs, long in_syscall)
|
|
{
|
|
if (test_thread_flag(TIF_SIGPENDING) ||
|
|
test_thread_flag(TIF_RESTORE_SIGMASK))
|
|
do_signal(regs, in_syscall);
|
|
|
|
if (test_thread_flag(TIF_NOTIFY_RESUME)) {
|
|
clear_thread_flag(TIF_NOTIFY_RESUME);
|
|
tracehook_notify_resume(regs);
|
|
if (current->replacement_session_keyring)
|
|
key_replace_session_keyring();
|
|
}
|
|
}
|