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[thirdparty/man-pages.git] / man7 / vdso.7

diff --git a/man7/vdso.7 b/man7/vdso.7
index b975c60df1926e8cb06b30caa1c806829f5b1bd1..9b426f823fd9bf3852f5eb34e12a9b4369e83e4d 100644 (file)
--- a/man7/vdso.7
+++ b/man7/vdso.7
@@ -10,7 +10,7 @@
 .\"   http://www.linuxjournal.com/content/creating-vdso-colonels-other-chicken
 .\"   http://www.trilithium.com/johan/2005/08/linux-gate/
 .\"
-.TH VDSO 7 2016-05-09 "Linux" "Linux Programmer's Manual"
+.TH VDSO 7 2019-08-02 "Linux" "Linux Programmer's Manual"
 .SH NAME
 vdso \- overview of the virtual ELF dynamic shared object
 .SH SYNOPSIS
@@ -57,7 +57,7 @@ the vDSO.
 Note that the terminology can be confusing.
 On x86 systems, the vDSO function
 used to determine the preferred method of making a system call is
-named "__kernel_vsyscall", but on x86_64,
+named "__kernel_vsyscall", but on x86-64,
 the term "vsyscall" also refers to an obsolete way to ask the kernel
 what time it is or what CPU the caller is on.
 .PP
@@ -132,7 +132,7 @@ When you compile the kernel,
 it will automatically compile and link the vDSO code for you.
 You will frequently find it under the architecture-specific directory:
 .PP
-    find arch/$ARCH/ -name '*vdso*.so*' -o -name '*gate*.so*'
+    find arch/$ARCH/ \-name \(aq*vdso*.so*\(aq \-o \-name \(aq*gate*.so*\(aq
 .\"
 .SS vDSO names
 The name of the vDSO varies across architectures.
@@ -147,29 +147,33 @@ The exact name should not matter to any code, so do not hardcode it.
 l l.
 user ABI       vDSO name
 _
-aarch64        linux-vdso.so.1
-arm    linux-vdso.so.1
-ia64   linux-gate.so.1
-mips   linux-vdso.so.1
-ppc/32 linux-vdso32.so.1
-ppc/64 linux-vdso64.so.1
-s390   linux-vdso32.so.1
-s390x  linux-vdso64.so.1
-sh     linux-gate.so.1
-i386   linux-gate.so.1
-x86_64 linux-vdso.so.1
-x86/x32        linux-vdso.so.1
+aarch64        linux\-vdso.so.1
+arm    linux\-vdso.so.1
+ia64   linux\-gate.so.1
+mips   linux\-vdso.so.1
+ppc/32 linux\-vdso32.so.1
+ppc/64 linux\-vdso64.so.1
+riscv  linux\-vdso.so.1
+s390   linux\-vdso32.so.1
+s390x  linux\-vdso64.so.1
+sh     linux\-gate.so.1
+i386   linux\-gate.so.1
+x86-64 linux\-vdso.so.1
+x86/x32        linux\-vdso.so.1
 .TE
 .if t \{\
 .in
 .ft P
 \}
-.SS strace(1) and the vDSO
+.SS strace(1), seccomp(2), and the vDSO
 When tracing systems calls with
 .BR strace (1),
 symbols (system calls) that are exported by the vDSO will
 .I not
 appear in the trace output.
+Those system calls will likewise not be visible to
+.BR seccomp (2)
+filters.
 .SH ARCHITECTURE-SPECIFIC NOTES
 The subsections below provide architecture-specific notes
 on the vDSO.
@@ -179,7 +183,7 @@ and not the ABI of the kernel.
 Thus, for example,
 when you run an i386 32-bit ELF binary,
 you'll get the same vDSO regardless of whether you run it under
-an i386 32-bit kernel or under an x86_64 64-bit kernel.
+an i386 32-bit kernel or under an x86-64 64-bit kernel.
 Therefore, the name of the user-space ABI should be used to determine
 which of the sections below is relevant.
 .SS ARM functions
@@ -231,7 +235,7 @@ __kernel_clock_getres       LINUX_2.6.39
 .in
 .ft P
 \}
-.SS bfin (Blackfin) functions
+.SS bfin (Blackfin) functions (port removed in Linux 4.17)
 .\" See linux/arch/blackfin/kernel/fixed_code.S
 .\" See http://docs.blackfin.uclinux.org/doku.php?id=linux-kernel:fixed-code
 As this CPU lacks a memory management unit (MMU),
@@ -319,7 +323,7 @@ set_tid_address
 .SS parisc (hppa) functions
 .\" See linux/arch/parisc/kernel/syscall.S
 .\" See linux/Documentation/parisc/registers
-The parisc port has a code page full of utility functions
+The parisc port has a code page with utility functions
 called a gateway page.
 Rather than use the normal ELF auxiliary vector approach,
 it passes the address of
@@ -341,21 +345,9 @@ for example:
 l l.
 offset function
 _
-00b0   lws_entry
-00e0   set_thread_pointer
+00b0   lws_entry (CAS operations)
+00e0   set_thread_pointer (used by glibc)
 0100   linux_gateway_entry (syscall)
-0268   syscall_nosys
-0274   tracesys
-0324   tracesys_next
-0368   tracesys_exit
-03a0   tracesys_sigexit
-03b8   lws_start
-03dc   lws_exit_nosys
-03e0   lws_exit
-03e4   lws_compare_and_swap64
-03e8   lws_compare_and_swap
-0404   cas_wouldblock
-0410   cas_action
 .TE
 .if t \{\
 .in
@@ -442,6 +434,27 @@ and
 .I __kernel_clock_gettime
 interfaces;
 the kernel falls back to the real system call.
+.SS riscv functions
+.\" See linux/arch/riscv/kernel/vdso/vdso.lds.S
+The table below lists the symbols exported by the vDSO.
+.if t \{\
+.ft CW
+\}
+.TS
+l l.
+symbol version
+_
+__kernel_rt_sigreturn  LINUX_4.15
+__kernel_gettimeofday  LINUX_4.15
+__kernel_clock_gettime LINUX_4.15
+__kernel_clock_getres  LINUX_4.15
+__kernel_getcpu        LINUX_4.15
+__kernel_flush_icache  LINUX_4.15
+.TE
+.if t \{\
+.in
+.ft P
+\}
 .SS s390 functions
 .\" See linux/arch/s390/kernel/vdso32/vdso32.lds.S
 The table below lists the symbols exported by the vDSO.
@@ -519,7 +532,7 @@ __vdso_time LINUX_2.6 (exported since Linux 3.15)
 .in
 .ft P
 \}
-.SS x86_64 functions
+.SS x86-64 functions
 .\" See linux/arch/x86/vdso/vdso.lds.S
 The table below lists the symbols exported by the vDSO.
 All of these symbols are also available without the "__vdso_" prefix, but
@@ -579,6 +592,6 @@ Documentation/ABI/stable/vdso
 Documentation/ia64/fsys.txt
 Documentation/vDSO/* (includes examples of using the vDSO)
 
-find arch/ -iname '*vdso*' -o -iname '*gate*'
+find arch/ \-iname \(aq*vdso*\(aq \-o \-iname \(aq*gate*\(aq
 .EE
 .in