[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[PATCH v5 11/20] linux-user/i386: Add vdso
|
From: |
Richard Henderson |
|
Subject: |
[PATCH v5 11/20] linux-user/i386: Add vdso |
|
Date: |
Tue, 29 Aug 2023 15:02:19 -0700 |
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1267
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
linux-user/i386/vdso-asmoffset.h | 6 ++
linux-user/elfload.c | 16 +++-
linux-user/i386/signal.c | 11 +++
linux-user/i386/meson.build | 24 ++++++
linux-user/i386/vdso.S | 143 +++++++++++++++++++++++++++++++
linux-user/i386/vdso.ld | 76 ++++++++++++++++
linux-user/i386/vdso.so | Bin 0 -> 2672 bytes
7 files changed, 274 insertions(+), 2 deletions(-)
create mode 100644 linux-user/i386/vdso-asmoffset.h
create mode 100644 linux-user/i386/vdso.S
create mode 100644 linux-user/i386/vdso.ld
create mode 100755 linux-user/i386/vdso.so
diff --git a/linux-user/i386/vdso-asmoffset.h b/linux-user/i386/vdso-asmoffset.h
new file mode 100644
index 0000000000..4e5ee0dd49
--- /dev/null
+++ b/linux-user/i386/vdso-asmoffset.h
@@ -0,0 +1,6 @@
+/*
+ * offsetof(struct sigframe, sc.eip)
+ * offsetof(struct rt_sigframe, uc.tuc_mcontext.eip)
+ */
+#define SIGFRAME_SIGCONTEXT_eip 64
+#define RT_SIGFRAME_SIGCONTEXT_eip 220
diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index 2a6adebb4a..fb876ae30a 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -309,12 +309,24 @@ static void elf_core_copy_regs(target_elf_gregset_t
*regs, const CPUX86State *en
(*regs)[15] = tswapreg(env->regs[R_ESP]);
(*regs)[16] = tswapreg(env->segs[R_SS].selector & 0xffff);
}
-#endif
+
+/*
+ * i386 is the only target which supplies AT_SYSINFO for the vdso.
+ * All others only supply AT_SYSINFO_EHDR.
+ */
+#define DLINFO_ARCH_ITEMS 1
+#define ARCH_DLINFO NEW_AUX_ENT(AT_SYSINFO, vdso_info->entry);
+
+#include "vdso.c.inc"
+
+#define vdso_image_info() &vdso_image_info
+
+#endif /* TARGET_X86_64 */
#define USE_ELF_CORE_DUMP
#define ELF_EXEC_PAGESIZE 4096
-#endif
+#endif /* TARGET_I386 */
#ifdef TARGET_ARM
diff --git a/linux-user/i386/signal.c b/linux-user/i386/signal.c
index 60fa07d6f9..bc5d45302e 100644
--- a/linux-user/i386/signal.c
+++ b/linux-user/i386/signal.c
@@ -214,6 +214,17 @@ struct rt_sigframe {
};
#define TARGET_RT_SIGFRAME_FXSAVE_OFFSET ( \
offsetof(struct rt_sigframe, fpstate) + TARGET_FPSTATE_FXSAVE_OFFSET)
+
+/*
+ * Verify that vdso-asmoffset.h constants match.
+ */
+#include "i386/vdso-asmoffset.h"
+
+QEMU_BUILD_BUG_ON(offsetof(struct sigframe, sc.eip)
+ != SIGFRAME_SIGCONTEXT_eip);
+QEMU_BUILD_BUG_ON(offsetof(struct rt_sigframe, uc.tuc_mcontext.eip)
+ != RT_SIGFRAME_SIGCONTEXT_eip);
+
#else
struct rt_sigframe {
diff --git a/linux-user/i386/meson.build b/linux-user/i386/meson.build
index ee523019a5..d858bf1d77 100644
--- a/linux-user/i386/meson.build
+++ b/linux-user/i386/meson.build
@@ -3,3 +3,27 @@ syscall_nr_generators += {
arguments: [ meson.current_source_dir() / 'syscallhdr.sh',
'@INPUT@', '@OUTPUT@', '@EXTRA_ARGS@' ],
output: '@BASENAME@_nr.h')
}
+
+vdso_so = custom_target(output: 'vdso.so',
+ input: files('vdso.S', 'vdso.ld'),
+ depend_files: files('vdso-asmoffset.h'),
+ command: [
+ build_vdso_cmd,
+ '-B', meson.project_build_root(),
+ '-C', meson.current_source_dir(),
+ '-T', 'i386-linux-user',
+ '-o', '@OUTPUT@',
+ '--', '-m32', '-nostdlib', '-shared',
+ '-Wl,-h,linux-gate.so.1',
+ '-Wl,--build-id=sha1',
+ '-Wl,--hash-style=both',
+ '-Wl,-T,@INPUT1@',
+ '@INPUT0@'
+ ])
+
+vdso_inc = gen_vdso.process(vdso_so, extra_args: [
+ '-s', '__kernel_sigreturn',
+ '-r', '__kernel_rt_sigreturn'
+ ])
+
+linux_user_ss.add(when: 'TARGET_I386', if_true: vdso_inc)
diff --git a/linux-user/i386/vdso.S b/linux-user/i386/vdso.S
new file mode 100644
index 0000000000..e7a1f333a1
--- /dev/null
+++ b/linux-user/i386/vdso.S
@@ -0,0 +1,143 @@
+/*
+ * i386 linux replacement vdso.
+ *
+ * Copyright 2023 Linaro, Ltd.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include <asm/unistd.h>
+#include "vdso-asmoffset.h"
+
+.macro endf name
+ .globl \name
+ .type \name, @function
+ .size \name, . - \name
+.endm
+
+.macro vdso_syscall1 name, nr
+\name:
+ .cfi_startproc
+ mov %ebx, %edx
+ .cfi_register %ebx, %edx
+ mov 4(%esp), %ebx
+ mov $\nr, %eax
+ int $0x80
+ mov %edx, %ebx
+ ret
+ .cfi_endproc
+endf \name
+.endm
+
+.macro vdso_syscall2 name, nr
+\name:
+ .cfi_startproc
+ mov %ebx, %edx
+ .cfi_register %ebx, %edx
+ mov 4(%esp), %ebx
+ mov 8(%esp), %ecx
+ mov $\nr, %eax
+ int $0x80
+ mov %edx, %ebx
+ ret
+ .cfi_endproc
+endf \name
+.endm
+
+.macro vdso_syscall3 name, nr
+\name:
+ .cfi_startproc
+ push %ebx
+ .cfi_adjust_cfa_offset 4
+ .cfi_rel_offset %ebx, 0
+ mov 8(%esp), %ebx
+ mov 12(%esp), %ecx
+ mov 16(%esp), %edx
+ mov $\nr, %eax
+ int $0x80
+ pop %ebx
+ .cfi_adjust_cfa_offset -4
+ .cfi_restore %ebx
+ ret
+ .cfi_endproc
+endf \name
+.endm
+
+__kernel_vsyscall:
+ .cfi_startproc
+ int $0x80
+ ret
+ .cfi_endproc
+endf __kernel_vsyscall
+
+vdso_syscall2 __vdso_clock_gettime, __NR_clock_gettime
+vdso_syscall2 __vdso_clock_gettime64, __NR_clock_gettime64
+vdso_syscall2 __vdso_clock_getres, __NR_clock_getres
+vdso_syscall2 __vdso_gettimeofday, __NR_gettimeofday
+vdso_syscall1 __vdso_time, __NR_time
+vdso_syscall3 __vdso_getcpu, __NR_gettimeofday
+
+/*
+ * Signal return handlers.
+ */
+
+ .cfi_startproc simple
+ .cfi_signal_frame
+
+/*
+ * For convenience, put the cfa just above eip in sigcontext, and count
+ * offsets backward from there. Re-compute the cfa in the two contexts
+ * we have for signal unwinding. This is far simpler than the
+ * DW_CFA_expression form that the kernel uses, and is equally correct.
+ */
+
+ .cfi_def_cfa %esp, SIGFRAME_SIGCONTEXT_eip + 4
+
+ .cfi_offset %eip, -4
+ /* err, -8 */
+ /* trapno, -12 */
+ .cfi_offset %eax, -16
+ .cfi_offset %ecx, -20
+ .cfi_offset %edx, -24
+ .cfi_offset %ebx, -28
+ .cfi_offset %esp, -32
+ .cfi_offset %ebp, -36
+ .cfi_offset %esi, -40
+ .cfi_offset %edi, -44
+
+/*
+ * While this frame is marked as a signal frame, that only applies to how
+ * the return address is handled for the outer frame. 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.
+ */
+ nop
+
+__kernel_sigreturn:
+ popl %eax /* pop sig */
+ .cfi_adjust_cfa_offset -4
+ movl $__NR_sigreturn, %eax
+ int $0x80
+endf __kernel_sigreturn
+
+ .cfi_def_cfa_offset RT_SIGFRAME_SIGCONTEXT_eip + 4
+ nop
+
+__kernel_rt_sigreturn:
+ movl $__NR_rt_sigreturn, %eax
+ int $0x80
+endf __kernel_rt_sigreturn
+
+ .cfi_endproc
+
+/*
+ * TODO: Add elf notes. E.g.
+ *
+ * #include <linux/elfnote.h>
+ * ELFNOTE_START(Linux, 0, "a")
+ * .long LINUX_VERSION_CODE
+ * ELFNOTE_END
+ *
+ * but what version number would we set for QEMU?
+ */
diff --git a/linux-user/i386/vdso.ld b/linux-user/i386/vdso.ld
new file mode 100644
index 0000000000..326b7a8f98
--- /dev/null
+++ b/linux-user/i386/vdso.ld
@@ -0,0 +1,76 @@
+/*
+ * Linker script for linux i386 replacement vdso.
+ *
+ * Copyright 2023 Linaro, Ltd.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+ENTRY(__kernel_vsyscall)
+
+VERSION {
+ LINUX_2.6 {
+ global:
+ __vdso_clock_gettime;
+ __vdso_gettimeofday;
+ __vdso_time;
+ __vdso_clock_getres;
+ __vdso_clock_gettime64;
+ __vdso_getcpu;
+ };
+
+ LINUX_2.5 {
+ global:
+ __kernel_vsyscall;
+ __kernel_sigreturn;
+ __kernel_rt_sigreturn;
+ local: *;
+ };
+}
+
+PHDRS {
+ phdr PT_PHDR FLAGS(4) PHDRS;
+ load PT_LOAD FLAGS(7) FILEHDR PHDRS; /* FLAGS=RWX */
+ dynamic PT_DYNAMIC FLAGS(4);
+ eh_frame_hdr PT_GNU_EH_FRAME;
+ note PT_NOTE FLAGS(4);
+}
+
+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 =0x90909090
+}
diff --git a/linux-user/i386/vdso.so b/linux-user/i386/vdso.so
new file mode 100755
index
0000000000000000000000000000000000000000..bdece5dfcf8da036d013262d4e37208350283cfa
GIT binary patch
literal 2672
zcmbtWU1%It6u#5lG_z^4ZB?X_C>9o5sxCF8QBlyONt?nZ)?|y73e)ZGba%;SR(597
zjTXE8QIiHtY6YPbDhO>6s(mPS(FX(Z2Q`g?1xp_^KInr_=|f8&)b;yj=5}w=eGok1
z%XiMX=brmB_ny0ldSlx(O%qZAA|PnR8-(ZpuhYGj4)L&P5F5p65f&@qVw=PV(21ar
zS~fT!zaSUUNMnr<D?qmul%W%{|IXi?lnz58hBiXBldmd>Kqu7p`(Ouv?E|~S#J4vR
z?eBj&+ji~rg~eZ!zf~VSJr_pXM}D8DFrl0ORPzVHn5LKmbB!e|qzOC^tO77~@mIB)
zzl6kpgPDI3e2U8d6uIY2bq_`x0-wZWxDMLSfe$J6M%crOeHivUY<@1rr@`l7bI!EC
z1WQ>fZdBic@iW@_P1t@f_$4LZXEGSfcpH2f?e~Kj&v`Zj+$T!NBlkb|jQhnHeiL+a
z&lJb<kCS@_*v@tHJTOn=lluBDy{$|iW0~jDvC(tlyVi??Q=2p0KUP})m@B{A^3Fp?
z#y5Ta$e&ZC6Ayg2)jAG+!^M53FpOcdV3|2%)E={wiChkz(UhGxlDT|x*hrg>lO18$
z-OkRAyW9oSmOj5{et#-4CVgruv?pIJqQxKI&ZY~dQ!H3DSHUrA-dxrymL5+h95ZU?
zqfdy~j)7gfjrM5g9c>HN9>C7<kIZ}NS==-4@5JK#YMzfafM=QF?WZPg6+aHhHu){t
z#@l_<Z)3bX7g}rJnLgP3J~0HQz%PJH;3Rk&d;okNJPDowp8;P3e*#_ve+BLUI4(td
zZBS?jb*;5I7#xS6XOVMV0Ql`GjNJ_U;OnA06ySNFpY!>?j(;zF-_-GQuCsOgock95
z$CvrnLFHO513c5BE36+~5f2BEAVM30`47nj^o(oe;NgZND~~oF)87oe)%5l%caD!C
zZUR`#4&CABw}%(BE9KdV>yxiUf|Id`UI}64SIQGVslJnSd`)$H14yd$t+Ysc2<dgC
zZ=Q@t)>OQ(J+srhD+k<&>B<F{@o$-65V!Wyt>HxRj<L>q5)uze70i3T0nE36-;4MD
zX|P(C`eCbeVGnF6>~F$Q>&)x0)jBo>TdiYfVXJlMbJ%KKV=Y$enlO4^9_Z@du@yHB
zwchCMGqw$O_4gWmJ%e{HQ)lfOF0TyrZnl4$<)z$G>%HU>FE1lXy;xFj>Xa70cGRgB
zZe?<tMbsV}aT5E$PQl}h)U3Q?ifC%gN{nQau7X$*O<ToiCShkhk5lkGqh`U*=B*`$
zkrGieW9%;^Moc4<LZq}r)G<pAcKN?aE5cZ-d1tTskoO0sTmQ-H0oHh)quV~pVEQOL
zf~-B80KOf}$M=_*fzCLdUB>YqcLID@7{~XU=z-4s6vh$lz%9JdjN|)G?1a8N?pfc*
zIKKY`&zcmDP2m_-KOf(Hg0)2EV}IgBfWHx_^Y;P~hc5SkbEE79n459x?;V(~$T$m@
zjElobxDGGOT`N`AK*n(#-do~0bSZKjGMDr(AZ`H$D-74d^xS8@>$IiJAn|o+fMq_`
OKQ-<Y4#gXF;{FA}h_Ctp
literal 0
HcmV?d00001
--
2.34.1
- [PATCH v5 00/20] linux-user: Implement VDSOs, Richard Henderson, 2023/08/29
- [PATCH v5 13/20] linux-user/aarch64: Add vdso, Richard Henderson, 2023/08/29
- [PATCH v5 11/20] linux-user/i386: Add vdso,
Richard Henderson <=
- [PATCH v5 14/20] linux-user/arm: Add vdso, Richard Henderson, 2023/08/29
- [PATCH v5 04/20] linux-user: Do not clobber bprm_buf swapping ehdr, Richard Henderson, 2023/08/29
- [PATCH v5 16/20] linux-user/riscv: Add vdso, Richard Henderson, 2023/08/29
- [PATCH v5 01/20] tests/docker: Update docker-loongarch-cross toolchain, Richard Henderson, 2023/08/29
- [PATCH v5 03/20] linux-user: Tidy loader_exec, Richard Henderson, 2023/08/29
- [PATCH v5 17/20] linux-user/loongarch64: Add vdso, Richard Henderson, 2023/08/29
- [PATCH v5 06/20] linux-user: Use ImageSource in load_symbols, Richard Henderson, 2023/08/29
- [PATCH v5 09/20] linux-user: Add gen-vdso tool, Richard Henderson, 2023/08/29
- [PATCH v5 10/20] linux-user: Add build-vdso.sh tool, Richard Henderson, 2023/08/29