From: "Philippe Mathieu-Daudé" <philmd@linaro.org>
To: Richard Henderson <richard.henderson@linaro.org>, qemu-devel@nongnu.org
Cc: alex.bennee@linaro.org, laurent@vivier.eu, Helge Deller <deller@gmx.de>
Subject: Re: [PATCH v6 13/19] linux-user/hppa: Add vdso
Date: Thu, 5 Oct 2023 18:16:53 +0200 [thread overview]
Message-ID: <b4dc7d22-ff3e-12a2-97d6-ce9448f3f527@linaro.org> (raw)
In-Reply-To: <20230930021529.987950-14-richard.henderson@linaro.org>
On 30/9/23 04:15, Richard Henderson wrote:
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
> linux-user/hppa/vdso-asmoffset.h | 12 +++
> linux-user/elfload.c | 2 +
> linux-user/hppa/signal.c | 24 +++--
> linux-user/hppa/Makefile.vdso | 11 +++
> linux-user/hppa/meson.build | 5 +
> linux-user/hppa/vdso.S | 165 +++++++++++++++++++++++++++++++
> linux-user/hppa/vdso.ld | 77 +++++++++++++++
> linux-user/hppa/vdso.so | Bin 0 -> 2104 bytes
> 8 files changed, 286 insertions(+), 10 deletions(-)
> create mode 100644 linux-user/hppa/vdso-asmoffset.h
> create mode 100644 linux-user/hppa/Makefile.vdso
> create mode 100644 linux-user/hppa/vdso.S
> create mode 100644 linux-user/hppa/vdso.ld
> create mode 100755 linux-user/hppa/vdso.so
The overall LGTM, so:
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Cc'ing Helge who have better knowledge of HPPA.
> diff --git a/linux-user/hppa/vdso-asmoffset.h b/linux-user/hppa/vdso-asmoffset.h
> new file mode 100644
> index 0000000000..c8b40c0332
> --- /dev/null
> +++ b/linux-user/hppa/vdso-asmoffset.h
> @@ -0,0 +1,12 @@
> +#define sizeof_rt_sigframe 584
> +#define offsetof_sigcontext 160
> +#define offsetof_sigcontext_gr 0x4
> +#define offsetof_sigcontext_fr 0x88
> +#define offsetof_sigcontext_iaoq 0x190
> +#define offsetof_sigcontext_sar 0x198
> +
> +/* arch/parisc/include/asm/rt_sigframe.h */
> +#define SIGFRAME 64
> +#define FUNCTIONCALLFRAME 48
> +#define PARISC_RT_SIGFRAME_SIZE32 \
> + (((sizeof_rt_sigframe) + FUNCTIONCALLFRAME + SIGFRAME) & -SIGFRAME)
> diff --git a/linux-user/elfload.c b/linux-user/elfload.c
> index a65401f8d5..ccf8a1dc78 100644
> --- a/linux-user/elfload.c
> +++ b/linux-user/elfload.c
> @@ -1921,6 +1921,8 @@ static inline void init_thread(struct target_pt_regs *regs,
> #define STACK_GROWS_DOWN 0
> #define STACK_ALIGNMENT 64
>
> +#define VDSO_HEADER "vdso.c.inc"
> +
> static inline void init_thread(struct target_pt_regs *regs,
> struct image_info *infop)
> {
> diff --git a/linux-user/hppa/signal.c b/linux-user/hppa/signal.c
> index bda6e54655..741dac79b6 100644
> --- a/linux-user/hppa/signal.c
> +++ b/linux-user/hppa/signal.c
> @@ -21,6 +21,7 @@
> #include "user-internals.h"
> #include "signal-common.h"
> #include "linux-user/trace.h"
> +#include "vdso-asmoffset.h"
>
> struct target_sigcontext {
> abi_ulong sc_flags;
> @@ -47,6 +48,19 @@ struct target_rt_sigframe {
> /* hidden location of upper halves of pa2.0 64-bit gregs */
> };
>
> +QEMU_BUILD_BUG_ON(sizeof(struct target_rt_sigframe) != sizeof_rt_sigframe);
> +QEMU_BUILD_BUG_ON(offsetof(struct target_rt_sigframe, uc.tuc_mcontext)
> + != offsetof_sigcontext);
> +QEMU_BUILD_BUG_ON(offsetof(struct target_sigcontext, sc_gr)
> + != offsetof_sigcontext_gr);
> +QEMU_BUILD_BUG_ON(offsetof(struct target_sigcontext, sc_fr)
> + != offsetof_sigcontext_fr);
> +QEMU_BUILD_BUG_ON(offsetof(struct target_sigcontext, sc_iaoq)
> + != offsetof_sigcontext_iaoq);
> +QEMU_BUILD_BUG_ON(offsetof(struct target_sigcontext, sc_sar)
> + != offsetof_sigcontext_sar);
> +
> +
> static void setup_sigcontext(struct target_sigcontext *sc, CPUArchState *env)
> {
> int i;
> @@ -91,16 +105,6 @@ static void restore_sigcontext(CPUArchState *env, struct target_sigcontext *sc)
> __get_user(env->cr[CR_SAR], &sc->sc_sar);
> }
>
> -#if TARGET_ABI_BITS == 32
> -#define SIGFRAME 64
> -#define FUNCTIONCALLFRAME 48
> -#else
> -#define SIGFRAME 128
> -#define FUNCTIONCALLFRAME 96
> -#endif
> -#define PARISC_RT_SIGFRAME_SIZE32 \
> - ((sizeof(struct target_rt_sigframe) + FUNCTIONCALLFRAME + SIGFRAME) & -SIGFRAME)
> -
> void setup_rt_frame(int sig, struct target_sigaction *ka,
> target_siginfo_t *info,
> target_sigset_t *set, CPUArchState *env)
> diff --git a/linux-user/hppa/Makefile.vdso b/linux-user/hppa/Makefile.vdso
> new file mode 100644
> index 0000000000..f4537ae716
> --- /dev/null
> +++ b/linux-user/hppa/Makefile.vdso
> @@ -0,0 +1,11 @@
> +include $(BUILD_DIR)/tests/tcg/hppa-linux-user/config-target.mak
> +
> +SUBDIR = $(SRC_PATH)/linux-user/hppa
> +VPATH += $(SUBDIR)
> +
> +all: $(SUBDIR)/vdso.so
> +
> +$(SUBDIR)/vdso.so: vdso.S vdso.ld vdso-asmoffset.h
> + $(CC) -o $@ -nostdlib -shared -Wl,-h,linux-vdso32.so.1 \
> + -Wl,--build-id=sha1 -Wl,--hash-style=both \
> + -Wl,-T,$(SUBDIR)/vdso.ld $<
> diff --git a/linux-user/hppa/meson.build b/linux-user/hppa/meson.build
> index 4709508a09..aa2d9a87a6 100644
> --- a/linux-user/hppa/meson.build
> +++ b/linux-user/hppa/meson.build
> @@ -3,3 +3,8 @@ syscall_nr_generators += {
> arguments: [ meson.current_source_dir() / 'syscallhdr.sh', '@INPUT@', '@OUTPUT@', '@EXTRA_ARGS@' ],
> output: '@BASENAME@_nr.h')
> }
> +
> +vdso_inc = gen_vdso.process('vdso.so',
> + extra_args: [ '-r', '__kernel_sigtramp_rt' ])
> +
> +linux_user_ss.add(when: 'TARGET_HPPA', if_true: vdso_inc)
> diff --git a/linux-user/hppa/vdso.S b/linux-user/hppa/vdso.S
> new file mode 100644
> index 0000000000..5be14d2f70
> --- /dev/null
> +++ b/linux-user/hppa/vdso.S
> @@ -0,0 +1,165 @@
> +/*
> + * hppa linux kernel vdso replacement.
> + *
> + * Copyright 2023 Linaro, Ltd.
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +
> +#include <asm/unistd.h>
> +#include "vdso-asmoffset.h"
> +
> + .text
> +
> +
> +/*
> + * arch/parisc/kernel/vdso32/sigtramp.S:
> + * Gdb expects the trampoline is on the stack and the pc is offset from
> + * a 64-byte boundary by 0, 4 or 5 instructions. Since the vdso trampoline
> + * is not on the stack, we need a new variant with different offsets and
> + * data to tell gdb where to find the signal context on the stack.
> + *
> + * Here we put the offset to the context data at the start of the trampoline
> + * region and offset the first trampoline by 2 instructions. Please do
> + * not change the trampoline as the code in gdb depends on the following
> + * instruction sequence exactly.
> + */
> +
> +/* arch/parisc/kernel/asm-offsets.c */
> +#define SIGFRAME_CONTEXT_REGS32 \
> + (offsetof_sigcontext - PARISC_RT_SIGFRAME_SIZE32)
> +
> + .align 64
> + .word SIGFRAME_CONTEXT_REGS32
> +
> +/*
> + * All that said, we can provide a proper unwind record, which means that
> + * GDB should not actually need the offset magic.
> + *
> + * The return address that arrived here, from the inner frame, is
> + * not marked as a signal frame and so the unwinder still tries to
> + * subtract 1 to examine the presumed call insn. Thus we must
> + * extend the unwind info to a nop before the start.
> + */
> +
> + .cfi_startproc simple
> + .cfi_signal_frame
> +
> + /* Compare pa32_fallback_frame_state from libgcc. */
> +
> + /*
> + * Place the CFA at the start of sigcontext for convenience.
> + * The previous CFA will be restored from the saved stack pointer.
> + */
> + .cfi_def_cfa 30, -PARISC_RT_SIGFRAME_SIZE32 + offsetof_sigcontext
> +
> + /* Record save offset of general registers. */
> + .cfi_offset 1, offsetof_sigcontext_gr + 1 * 4
> + .cfi_offset 2, offsetof_sigcontext_gr + 2 * 4
> + .cfi_offset 3, offsetof_sigcontext_gr + 3 * 4
> + .cfi_offset 4, offsetof_sigcontext_gr + 4 * 4
> + .cfi_offset 5, offsetof_sigcontext_gr + 5 * 4
> + .cfi_offset 6, offsetof_sigcontext_gr + 6 * 4
> + .cfi_offset 7, offsetof_sigcontext_gr + 7 * 4
> + .cfi_offset 8, offsetof_sigcontext_gr + 8 * 4
> + .cfi_offset 9, offsetof_sigcontext_gr + 9 * 4
> + .cfi_offset 10, offsetof_sigcontext_gr + 10 * 4
> + .cfi_offset 11, offsetof_sigcontext_gr + 11 * 4
> + .cfi_offset 12, offsetof_sigcontext_gr + 12 * 4
> + .cfi_offset 13, offsetof_sigcontext_gr + 13 * 4
> + .cfi_offset 14, offsetof_sigcontext_gr + 14 * 4
> + .cfi_offset 15, offsetof_sigcontext_gr + 15 * 4
> + .cfi_offset 16, offsetof_sigcontext_gr + 16 * 4
> + .cfi_offset 17, offsetof_sigcontext_gr + 17 * 4
> + .cfi_offset 18, offsetof_sigcontext_gr + 18 * 4
> + .cfi_offset 19, offsetof_sigcontext_gr + 19 * 4
> + .cfi_offset 20, offsetof_sigcontext_gr + 20 * 4
> + .cfi_offset 21, offsetof_sigcontext_gr + 21 * 4
> + .cfi_offset 22, offsetof_sigcontext_gr + 22 * 4
> + .cfi_offset 23, offsetof_sigcontext_gr + 23 * 4
> + .cfi_offset 24, offsetof_sigcontext_gr + 24 * 4
> + .cfi_offset 25, offsetof_sigcontext_gr + 25 * 4
> + .cfi_offset 26, offsetof_sigcontext_gr + 26 * 4
> + .cfi_offset 27, offsetof_sigcontext_gr + 27 * 4
> + .cfi_offset 28, offsetof_sigcontext_gr + 28 * 4
> + .cfi_offset 29, offsetof_sigcontext_gr + 29 * 4
> + .cfi_offset 30, offsetof_sigcontext_gr + 30 * 4
> + .cfi_offset 31, offsetof_sigcontext_gr + 31 * 4
> +
> + /* Record save offset of fp registers, left and right halves. */
> + .cfi_offset 32, offsetof_sigcontext_fr + 4 * 8
> + .cfi_offset 33, offsetof_sigcontext_fr + 4 * 8 + 4
> + .cfi_offset 34, offsetof_sigcontext_fr + 5 * 8
> + .cfi_offset 35, offsetof_sigcontext_fr + 5 * 8 + 4
> + .cfi_offset 36, offsetof_sigcontext_fr + 6 * 8
> + .cfi_offset 37, offsetof_sigcontext_fr + 6 * 8 + 4
> + .cfi_offset 38, offsetof_sigcontext_fr + 7 * 8
> + .cfi_offset 39, offsetof_sigcontext_fr + 7 * 8 + 4
> + .cfi_offset 40, offsetof_sigcontext_fr + 8 * 8
> + .cfi_offset 41, offsetof_sigcontext_fr + 8 * 8 + 4
> + .cfi_offset 42, offsetof_sigcontext_fr + 9 * 8
> + .cfi_offset 43, offsetof_sigcontext_fr + 9 * 8 + 4
> + .cfi_offset 44, offsetof_sigcontext_fr + 10 * 8
> + .cfi_offset 45, offsetof_sigcontext_fr + 10 * 8 + 4
> + .cfi_offset 46, offsetof_sigcontext_fr + 11 * 8
> + .cfi_offset 47, offsetof_sigcontext_fr + 11 * 8 + 4
> + .cfi_offset 48, offsetof_sigcontext_fr + 12 * 8
> + .cfi_offset 49, offsetof_sigcontext_fr + 12 * 8 + 4
> + .cfi_offset 50, offsetof_sigcontext_fr + 13 * 8
> + .cfi_offset 51, offsetof_sigcontext_fr + 13 * 8 + 4
> + .cfi_offset 52, offsetof_sigcontext_fr + 14 * 8
> + .cfi_offset 53, offsetof_sigcontext_fr + 14 * 8 + 4
> + .cfi_offset 54, offsetof_sigcontext_fr + 15 * 8
> + .cfi_offset 55, offsetof_sigcontext_fr + 15 * 8 + 4
> + .cfi_offset 56, offsetof_sigcontext_fr + 16 * 8
> + .cfi_offset 57, offsetof_sigcontext_fr + 16 * 8 + 4
> + .cfi_offset 58, offsetof_sigcontext_fr + 17 * 8
> + .cfi_offset 59, offsetof_sigcontext_fr + 17 * 8 + 4
> + .cfi_offset 60, offsetof_sigcontext_fr + 18 * 8
> + .cfi_offset 61, offsetof_sigcontext_fr + 18 * 8 + 4
> + .cfi_offset 62, offsetof_sigcontext_fr + 19 * 8
> + .cfi_offset 63, offsetof_sigcontext_fr + 19 * 8 + 4
> + .cfi_offset 64, offsetof_sigcontext_fr + 20 * 8
> + .cfi_offset 65, offsetof_sigcontext_fr + 20 * 8 + 4
> + .cfi_offset 66, offsetof_sigcontext_fr + 21 * 8
> + .cfi_offset 67, offsetof_sigcontext_fr + 21 * 8 + 4
> + .cfi_offset 68, offsetof_sigcontext_fr + 22 * 8
> + .cfi_offset 69, offsetof_sigcontext_fr + 22 * 8 + 4
> + .cfi_offset 70, offsetof_sigcontext_fr + 23 * 8
> + .cfi_offset 71, offsetof_sigcontext_fr + 23 * 8 + 4
> + .cfi_offset 72, offsetof_sigcontext_fr + 24 * 8
> + .cfi_offset 73, offsetof_sigcontext_fr + 24 * 8 + 4
> + .cfi_offset 74, offsetof_sigcontext_fr + 25 * 8
> + .cfi_offset 75, offsetof_sigcontext_fr + 25 * 8 + 4
> + .cfi_offset 76, offsetof_sigcontext_fr + 26 * 8
> + .cfi_offset 77, offsetof_sigcontext_fr + 26 * 8 + 4
> + .cfi_offset 78, offsetof_sigcontext_fr + 27 * 8
> + .cfi_offset 79, offsetof_sigcontext_fr + 27 * 8 + 4
> + .cfi_offset 80, offsetof_sigcontext_fr + 28 * 8
> + .cfi_offset 81, offsetof_sigcontext_fr + 28 * 8 + 4
> + .cfi_offset 82, offsetof_sigcontext_fr + 29 * 8
> + .cfi_offset 83, offsetof_sigcontext_fr + 29 * 8 + 4
> + .cfi_offset 84, offsetof_sigcontext_fr + 30 * 8
> + .cfi_offset 85, offsetof_sigcontext_fr + 30 * 8 + 4
> + .cfi_offset 86, offsetof_sigcontext_fr + 31 * 8
> + .cfi_offset 87, offsetof_sigcontext_fr + 31 * 8 + 4
> +
> + /* Record save offset of %sar */
> + .cfi_offset 88, offsetof_sigcontext_sar
> +
> + /* Record save offset of return address, iaoq[0]. */
> + .cfi_return_column 89
> + .cfi_offset 89, offsetof_sigcontext_iaoq
> +
> + nop
> +
> +__kernel_sigtramp_rt:
> + ldi 0, %r25
> + ldi __NR_rt_sigreturn, %r20
> + be,l 0x100(%sr2, %r0), %sr0, %r31
> + nop
> +
> + .cfi_endproc
> + .size __kernel_sigtramp_rt, . - __kernel_sigtramp_rt
> + .type __kernel_sigtramp_rt, @function
> + .globl __kernel_sigtramp_rt
> diff --git a/linux-user/hppa/vdso.ld b/linux-user/hppa/vdso.ld
> new file mode 100644
> index 0000000000..b17ad974f3
> --- /dev/null
> +++ b/linux-user/hppa/vdso.ld
> @@ -0,0 +1,77 @@
> +/*
> + * Linker script for linux hppa vdso.
> + *
> + * This 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 of the License, or (at your option) any later version.
> + *
> + * This 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 this library; if not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +VERSION {
> + /*
> + * The kernel's vdso32.lds.S attempts to export
> + * __kernel_sigtramp_rt32
> + * __kernel_restart_syscall32
> + * except that those symbols don't exist. The actual symbols are
> + * __kernel_sigtramp_rt
> + * __kernel_restart_syscall
> + * which means that nothing is exported at all.
> + * QEMU handles syscall restart internally, so we don't
> + * need to implement __kernel_restart_syscall at all.
> + */
> + LINUX_5.18 {
> + local: *;
> + };
> +}
> +
> +
> +PHDRS {
> + phdr PT_PHDR FLAGS(4) PHDRS;
> + load PT_LOAD FLAGS(7) FILEHDR PHDRS;
> + dynamic PT_DYNAMIC FLAGS(4);
> + note PT_NOTE FLAGS(4);
> + eh_frame_hdr PT_GNU_EH_FRAME;
> +}
> +
> +SECTIONS {
> + . = SIZEOF_HEADERS;
> +
> + /* The following, including the FILEHDRS and PHDRS, are modified
> + when we relocate the binary. We want them to be initially
> + writable for the relocation; we'll force them read-only after. */
> + .note : { *(.note*) } :load :note
> + .dynamic : { *(.dynamic) } :load :dynamic
> + .dynsym : { *(.dynsym) } :load
> + .data : {
> + /* There ought not be any real read-write data.
> + But since we manipulated the segment layout,
> + we have to put these sections somewhere. */
> + *(.data*)
> + *(.sdata*)
> + *(.got.plt) *(.got)
> + *(.gnu.linkonce.d.*)
> + *(.bss*)
> + *(.dynbss*)
> + *(.gnu.linkonce.b.*)
> + }
> +
> + .rodata : { *(.rodata) }
> + .hash : { *(.hash) }
> + .gnu.hash : { *(.gnu.hash) }
> + .dynstr : { *(.dynstr) }
> + .gnu.version : { *(.gnu.version) }
> + .gnu.version_d : { *(.gnu.version_d) }
> + .gnu.version_r : { *(.gnu.version_r) }
> + .eh_frame_hdr : { *(.eh_frame_hdr) } :load :eh_frame_hdr
> + .eh_frame : { *(.eh_frame) } :load
> +
> + .text : { *(.text*) } :load
> +}
next prev parent reply other threads:[~2023-10-05 16:17 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-09-30 2:15 [PATCH v6 00/19] linux-user: Implement VDSOs Richard Henderson
2023-09-30 2:15 ` [PATCH v6 01/19] linux-user: Introduce imgsrc_read, imgsrc_read_alloc Richard Henderson
2023-09-30 2:15 ` [PATCH v6 02/19] linux-user: Tidy loader_exec Richard Henderson
2023-09-30 2:15 ` [PATCH v6 03/19] linux-user: Do not clobber bprm_buf swapping ehdr Richard Henderson
2023-09-30 2:15 ` [PATCH v6 04/19] linux-user: Use ImageSource in load_elf_image Richard Henderson
2023-10-02 13:22 ` Philippe Mathieu-Daudé
2023-09-30 2:15 ` [PATCH v6 05/19] linux-user: Use ImageSource in load_symbols Richard Henderson
2023-09-30 2:15 ` [PATCH v6 06/19] linux-user: Replace bprm->fd with bprm->src.fd Richard Henderson
2023-09-30 2:15 ` [PATCH v6 07/19] linux-user: Load vdso image if available Richard Henderson
2023-10-03 12:47 ` Philippe Mathieu-Daudé
2023-09-30 2:15 ` [PATCH v6 08/19] linux-user: Add gen-vdso tool Richard Henderson
2023-10-03 13:00 ` Philippe Mathieu-Daudé
2023-10-03 23:05 ` Richard Henderson
2023-10-05 16:25 ` Philippe Mathieu-Daudé
2023-09-30 2:15 ` [PATCH v6 09/19] linux-user/i386: Add vdso Richard Henderson
2023-10-05 16:42 ` Philippe Mathieu-Daudé
2023-09-30 2:15 ` [PATCH v6 10/19] linux-user/x86_64: " Richard Henderson
2023-10-05 16:44 ` Philippe Mathieu-Daudé
2023-09-30 2:15 ` [PATCH v6 11/19] linux-user/aarch64: " Richard Henderson
2023-10-05 16:47 ` Philippe Mathieu-Daudé
2023-09-30 2:15 ` [PATCH v6 12/19] linux-user/arm: " Richard Henderson
2023-09-30 2:15 ` [PATCH v6 13/19] linux-user/hppa: " Richard Henderson
2023-10-05 16:16 ` Philippe Mathieu-Daudé [this message]
2023-09-30 2:15 ` [PATCH v6 14/19] linux-user/riscv: " Richard Henderson
2023-10-05 16:24 ` Philippe Mathieu-Daudé
2023-09-30 2:15 ` [PATCH v6 15/19] linux-user/loongarch64: " Richard Henderson
2023-10-05 16:18 ` Philippe Mathieu-Daudé
2023-09-30 2:15 ` [PATCH v6 16/19] linux-user/ppc: " Richard Henderson
2023-10-05 16:35 ` Philippe Mathieu-Daudé
2023-09-30 2:15 ` [PATCH v6 17/19] linux-user/s390x: Rename __SIGNAL_FRAMESIZE to STACK_FRAME_OVERHEAD Richard Henderson
2023-09-30 2:15 ` [PATCH v6 18/19] linux-user/s390x: Add vdso Richard Henderson
2023-10-03 13:07 ` Philippe Mathieu-Daudé
2023-10-03 23:01 ` Richard Henderson
2023-10-05 16:14 ` Philippe Mathieu-Daudé
2023-10-06 7:30 ` Thomas Huth
2023-09-30 2:15 ` [PATCH v6 19/19] build: Add update-linux-vdso makefile rule Richard Henderson
2023-10-03 13:02 ` Philippe Mathieu-Daudé
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