On 14/04/2020 13:54, Stepan Golosunov wrote:
> 12.04.2020 в 19:33:21 +0400 Stepan Golosunov написал:
>> 03.04.2020 в 17:31:52 -0300 Adhemerval Zanella написал:
>>> This patch adds the sparc modifications required for the BZ#12683 fix.
>>>
>>> Different than other architectures, SPARC passes the sigcontext_t
>>> struct pointer as third argument in the signal handler set with
>>> SA_SIGINFO (some info at [1]) for 64 bits and the pt_regs in 32 bits.
>>> >From Linux code:
>>>
>>> * arch/sparc/kernel/signal_64.c
>>>
>>> 428 /* 3. signal handler back-trampoline and parameters */
>>> 429 regs->u_regs[UREG_FP] = ((unsigned long) sf) - STACK_BIAS;
>>> 430 regs->u_regs[UREG_I0] = ksig->sig;
>>> 431 regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
>>> 432
>>> 433 /* The sigcontext is passed in this way because of how it
>>> 434 * is defined in GLIBC's /usr/include/bits/sigcontext.h
>>> 435 * for sparc64. It includes the 128 bytes of siginfo_t.
>>> 436 */
>>> 437 regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
>>>
>>> * arch/sparc/kernel/signal_32.c:
>>>
>>> 392 regs->u_regs[UREG_FP] = (unsigned long) sf;
>>> 393 regs->u_regs[UREG_I0] = ksig->sig;
>>> 394 regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
>>> 395 regs->u_regs[UREG_I2] = (unsigned long) &sf->regs;
>>> 396
>>> 397 regs->pc = (unsigned long) ksig->ka.sa.sa_handler;
>>> 398 regs->npc = (regs->pc + 4);
>>>
>>> So it requires an arch-specific ucontext_add_cancel.
>>>
>>> Also on sparc interrupted pause syscall returns with a PC indicating a
>>> side-effect and this deviates from other architectures. The sparc64
>>> pause fall back to ppool syscall.
>>
>> s/ppool/ppoll/
>>
>>>
>>> Checked on sparc64-linux-gnu and sparcv9-linux-gnu.
>>>
>>> [1] https://www.spinics.net/lists/sparclinux/msg05037.html
>>> ---
>>> sysdeps/sparc/nptl/tcb-offsets.sym | 3 +
>>> .../sysv/linux/sparc/cancellation-sigmask.h | 39 ++++++++++
>>> .../sysv/linux/sparc/sparc32/syscall_cancel.S | 71 ++++++++++++++++++
>>> sysdeps/unix/sysv/linux/sparc/sparc64/pause.c | 25 +++++++
>>> .../sysv/linux/sparc/sparc64/syscall_cancel.S | 74 +++++++++++++++++++
>>> 5 files changed, 212 insertions(+)
>>> create mode 100644 sysdeps/unix/sysv/linux/sparc/cancellation-sigmask.h
>>> create mode 100644 sysdeps/unix/sysv/linux/sparc/sparc32/syscall_cancel.S
>>> create mode 100644 sysdeps/unix/sysv/linux/sparc/sparc64/pause.c
>>> create mode 100644 sysdeps/unix/sysv/linux/sparc/sparc64/syscall_cancel.S
>>
>>> --- /dev/null
>>> +++ b/sysdeps/unix/sysv/linux/sparc/sparc64/pause.c
>>> @@ -0,0 +1,25 @@
>>> +/* Linux pause syscall implementation. Linux/sparc64.
>>> + Copyright (C) 2020 Free Software Foundation, Inc.
>>> + This file is part of the GNU C Library.
>>> +
>>> + The GNU C Library is free software; you can redistribute it and/or
>>> + modify it under the terms of the GNU Lesser General Public
>>> + License as published by the Free Software Foundation; either
>>> + version 2.1 of the License, or (at your option) any later version.
>>> +
>>> + The GNU C Library is distributed in the hope that it will be useful,
>>> + but WITHOUT ANY WARRANTY; without even the implied warranty of
>>> + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
>>> + Lesser General Public License for more details.
>>> +
>>> + You should have received a copy of the GNU Lesser General Public
>>> + License along with the GNU C Library; if not, see
>>> + <http://www.gnu.org/licenses/>. */
>>> +
>>> +#include <sys/syscall.h>
>>> +
>>> +/* On sparc interrupted pause syscall returns with a PC indicating a
>>> + side-effect and this deviates from other architectures. Fall back to
>>> + ppool implementation. */
>>
>> ditto
>>
>>> +#undef __NR_pause
>>> +#include <sysdeps/unix/sysv/linux/pause.c>
>
> But sysdeps/unix/sysv/linux/sparc/kernel-features.h already contains
>
> #ifdef __arch64__
> /* sparc64 defines __NR_pause, however it is not supported (ENOSYS).
> Undefine so pause.c can use a correct alternative. */
> # undef __NR_pause
> #endif
>
Indeed, I already has pushed this fix on generic implementation. I have
removed the new pause implementation and fixed the commit message
accordingly.
@@ -4,3 +4,6 @@
MULTIPLE_THREADS_OFFSET offsetof (tcbhead_t, multiple_threads)
POINTER_GUARD offsetof (tcbhead_t, pointer_guard)
TID offsetof (struct pthread, tid)
+
+-- Not strictly offsets, used on syscall_cancel.S
+TCB_CANCELED_BITMASK CANCELED_BITMASK
new file mode 100644
@@ -0,0 +1,39 @@
+/* Architecture specific bits for cancellation handling.
+ Copyright (C) 2020 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#ifndef _NPTL_CANCELLATION_SIGMASK_H
+#define _NPTL_CANCELLATION_SIGMASK_H 1
+
+/* Add the SIGCANCEL signal on sigmask set at the ucontext CTX obtained from
+ the sigaction handler. */
+static void
+ucontext_block_sigcancel (void *ctx)
+{
+ sigset_t *set;
+#ifdef __arch64__
+ struct pt_regs *regs = (struct pt_regs*) ((siginfo_t *)(ctx) + 1);
+ __siginfo_fpu_t *f = (__siginfo_fpu_t *)(regs + 1);
+ set = (sigset_t *) ((stack_t *)(f + 1) + 1);
+#else
+ struct pt_regs32 *ptregs = (struct pt_regs32 *) (ctx);
+ set = (sigset_t *) (ptregs + 1);
+#endif
+ __sigaddset (set, SIGCANCEL);
+}
+
+#endif
new file mode 100644
@@ -0,0 +1,71 @@
+/* Cancellable syscall wrapper. Linux/sparc32 version.
+ Copyright (C) 2020 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <sysdep.h>
+
+/* long int __syscall_cancel_arch (int *cancelhandling,
+ long int nr,
+ long int arg1,
+ long int arg2,
+ long int arg3,
+ long int arg4,
+ long int arg5,
+ long int arg6) */
+
+ENTRY (__syscall_cancel_arch)
+ save %sp, -96, %sp
+
+ cfi_window_save
+ cfi_register (%o7, %i7)
+ cfi_def_cfa_register (%fp)
+
+ .globl __syscall_cancel_arch_start
+__syscall_cancel_arch_start:
+
+ /* if (*cancelhandling & CANCELED_BITMASK)
+ __syscall_do_cancel() */
+ ld [%i0], %g2
+ andcc %g2, TCB_CANCELED_BITMASK, %g0
+ bne,pn %icc, 2f
+ /* Issue a 6 argument syscall. */
+ mov %i1, %g1
+ mov %i2, %o0
+ mov %i3, %o1
+ mov %i4, %o2
+ mov %i5, %o3
+ ld [%fp+92], %o4
+ ld [%fp+96], %o5
+ ta 0x10
+
+ .globl __syscall_cancel_arch_end
+__syscall_cancel_arch_end:
+ bcc 1f
+ nop
+ sub %g0, %o0, %o0
+1:
+ mov %o0, %i0
+ return %i7+8
+ nop
+
+2:
+ call __syscall_do_cancel, 0
+ nop
+ nop
+
+END (__syscall_cancel_arch)
+libc_hidden_def (__syscall_cancel_arch)
new file mode 100644
@@ -0,0 +1,25 @@
+/* Linux pause syscall implementation. Linux/sparc64.
+ Copyright (C) 2020 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <sys/syscall.h>
+
+/* On sparc interrupted pause syscall returns with a PC indicating a
+ side-effect and this deviates from other architectures. Fall back to
+ ppool implementation. */
+#undef __NR_pause
+#include <sysdeps/unix/sysv/linux/pause.c>
new file mode 100644
@@ -0,0 +1,74 @@
+/* Cancellable syscall wrapper. Linux/sparc64 version.
+ Copyright (C) 2020 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <sysdep.h>
+
+ .register %g2, #scratch
+
+/* long int __syscall_cancel_arch (int *cancelhandling,
+ long int nr,
+ long int arg1,
+ long int arg2,
+ long int arg3,
+ long int arg4,
+ long int arg5,
+ long int arg6) */
+
+ENTRY (__syscall_cancel_arch)
+ save %sp, -176, %sp
+
+ cfi_window_save
+ cfi_register (%o7, %i7)
+ cfi_def_cfa_register (%fp)
+
+ .globl __syscall_cancel_arch_start
+__syscall_cancel_arch_start:
+
+ /* if (*cancelhandling & CANCELED_BITMASK)
+ __syscall_do_cancel() */
+ lduw [%i0], %g2
+ andcc %g2, TCB_CANCELED_BITMASK, %g0
+ bne,pn %xcc, 2f
+ /* Issue a 6 argument syscall. */
+ mov %i1, %g1
+ mov %i2, %o0
+ mov %i3, %o1
+ mov %i4, %o2
+ mov %i5, %o3
+ ldx [%fp + STACK_BIAS + 176], %o4
+ ldx [%fp + STACK_BIAS + 184], %o5
+ ta 0x6d
+
+ .global __syscall_cancel_arch_end
+__syscall_cancel_arch_end:
+
+ bcc,pt %xcc, 1f
+ nop
+ sub %g0, %o0, %o0
+1:
+ mov %o0, %i0
+ return %i7+8
+ nop
+
+2:
+ call __syscall_do_cancel, 0
+ nop
+ nop
+
+END (__syscall_cancel_arch)
+libc_hidden_def (__syscall_cancel_arch)