"We don't need it any more"
The INTR_MSG_TRAP macro in intr-msg.h used to play little trick with
the stack pointer: it would temporarily save the "real" stack pointer
into ecx, while setting esp to point to just before the message buffer,
and then invoke the mach_msg trap. This way, INTR_MSG_TRAP reused the
on-stack arguments laid out for the containing call of
_hurd_intr_rpc_mach_msg (), passing them to the mach_msg trap directly.
This, however, required special support in hurdsig.c and trampoline.c,
since they now had to recognize when a thread is inside the piece of
code where esp doesn't point to the real tip of the stack, and handle
this situation specially.
Commit 1d20f33ff4 has removed the actual
temporary change of esp by actually re-pushing mach_msg arguments onto
the stack, and popping them back at end. It did not, however, deal with
the rest of "the ecx kludge" code in other files, resulting in potential
crashes if a signal arrives in the middle of pushing arguments onto the
stack.
Fix that by removing "the ecx kludge". Instead, when we want a thread
to skip the RPC, but cannot make just make it jump to after the trap
since it's not done adjusting the stack yet, set the SYSRETURN register
to MACH_SEND_INTERRUPTED (as we do anyway), and rely on the thread
itself for detecting this case and skipping the RPC.
This simplifies things somewhat and paves the way for a future x86_64
port of this code.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230301162355.426887-1-bugaevc@gmail.com>
We used to use .cfi_adjust_cfa_offset around %esp manipulation
asm instructions to fix unwinding, but when building glibc with
-fno-omit-frame-pointer this is bogus since in that case %ebp is the CFA and
does not move.
Instead, let's force -fno-omit-frame-pointer when building intr-msg.c so
that %ebp can always be used and no .cfi_adjust_cfa_offset is needed.
I used these shell commands:
../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")
and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 7061 files FOO.
I then removed trailing white space from math/tgmath.h,
support/tst-support-open-dev-null-range.c, and
sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following
obscure pre-commit check failure diagnostics from Savannah. I don't
know why I run into these diagnostics whereas others evidently do not.
remote: *** 912-#endif
remote: *** 913:
remote: *** 914-
remote: *** error: lines with trailing whitespace found
...
remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
INTR_MSG_TRAP was tinkering with esp to make it point to
_hurd_intr_rpc_mach_msg's parameters, and notably use (&msg)[-1] which is
meaningless in C.
Instead, just push the parameters on the stack, which also avoids leaving
local variables of _hurd_intr_rpc_mach_msg below esp. We now also
properly express that OPTION and TIMEOUT may be updated during the trap
call.
I used these shell commands:
../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")
and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 6694 files FOO.
I then removed trailing white space from benchtests/bench-pthread-locks.c
and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this
diagnostic from Savannah:
remote: *** pre-commit check failed ...
remote: *** error: lines with trailing whitespace found
remote: error: hook declined to update refs/heads/master
* sysdeps/mach/hurd/i386/intr-msg.h (INTR_MSG_TRAP): Make
_hurd_intr_rpc_msg_about_to global point to start of controlled
assembly snippet. Make it check canceled flag.
* hurd/hurdsig.c (_hurdsig_abort_rpcs): Only mutate thread if it passed
the _hurd_intr_rpc_msg_about_to point.
* hurd/intr-msg.c (_hurd_intr_rpc_mach_msg): Remove comment on mutation
issue, remove cancel flag check.
* sysdeps/mach/hurd/Makefile ($(common-objpfx)errnos.d): Depend on
libc-modules.h
* sysdeps/mach/hurd/i386/trampoline.c (_hurd_setup_sighandler): Remove
unused declaration of _hurd_intr_rpc_msg_in_trap.
* mach/mach_init.c (__mach_init): Test whether HAVE_HOST_PAGE_SIZE is
defined instead of whether it is non-zero.
* sysdeps/mach/hurd/i386/intr-msg.h (INTR_MSG_TRAP): Use "+m"
input constraint instead of both input and output constraint. Use ecx
clobber instead of %ecx.
* sysdeps/mach/hurd/malloc-machine.h (mutex_init, mutex_lock,
mutex_unlock): Use a statement expression instead of an expression list.
* sysdeps/mach/hurd/setitimer.c (_hurd_itimer_thread_stack_size): Set
type to vm_size_t instead of vm_address_t.
* sysdeps/mach/hurd/fork.c (__fork): Test whether STACK_GROWTH_UP is
defined instead of whether it is non-zero.
* hurd/hurd/ioctl.h (_hurd_locked_install_cttyid): New declaration.
* sysdeps/mach/hurd/setsid.c: Include <hurd/ioctl.h>.
* sysdeps/mach/hurd/mmap.c (__mmap): Use 0 instead of NULL for
comparisons with mapaddr.
* nscd/nscd-client.h: Include <time.h>.
* sysdeps/mach/hurd/dl-sysdep.c (fmh): Pass vm_offset_t dummy
9th parameter to __vm_region instead of int.
2001-07-06 Paul Eggert <eggert@twinsun.com>
* manual/argp.texi: Remove ignored LGPL copyright notice; it's
not appropriate for documentation anyway.
* manual/libc-texinfo.sh: "Library General Public License" ->
"Lesser General Public License".
2001-07-06 Andreas Jaeger <aj@suse.de>
* All files under GPL/LGPL version 2: Place under LGPL version
2.1.
options after $(build-module), which is no longer a single command.
(LDFLAGS-link-rpcuserlibs): New variable to hold those options.
(LDFLAGS-libmachuser-link.so, LDFLAGS-libhurduser-link.so): New
variables using it. Reported by Mark Kettenis <kettenis@gnu.org>.
2001-03-11 Roland McGrath <roland@frob.com>
* elf/rtld.c (dl_main): Add cast to quiet warning.
* elf/dl-load.c (_dl_map_object_from_fd): Likewise.
* iconv/gconv_conf.c (__gconv_get_path): Likewise.
(__gconv_read_conf): Likewise.
* iconv/gconv_db.c (gen_steps): Likewise.
(__gconv_find_transform): Likewise.
* locale/programs/charmap-dir.c (fopen_uncompressed): Likewise.
(fopen_uncompressed): Use const in second argument's type.
2001-03-11 Roland McGrath <roland@frob.com>
* sysdeps/mach/hurd/dl-sysdep.c (__writev): New function.
* mach/mach_error.h: Fix ancient #endif syntax.
* hurd/hurdmalloc.c: Likewise.
* sysdeps/generic/atomicity.h (exchange_and_add, atomic_add,
compare_and_swap): Add volatile qualifier to first arg, to bring
these prototypes in line with all the other implementations.
Add a #warning to remind the builder that these are not atomic.
2001-03-04 Roland McGrath <roland@frob.com>
* hurd/vpprintf.c (vpprintf) [USE_IN_LIBIO]: Use innermore first
member of TEMP_F so its type is _IO_FILE * as expected.
* hurd/fopenport.c (seekio): Conditionalize type of POS argument
on [USE_IN_LIBIO]. Check the value for overflow, since for libio
it might exceed off_t's range.
2001-02-25 Roland McGrath <roland@frob.com>
* sysdeps/mach/hurd/sysd-stdio.c (__stdio_reopen): Use prototype.
* sysdeps/unix/bsd/getpt.c (__posix_openpt): Likewise.
* sysdeps/mach/hurd/i386/intr-msg.h (SYSCALL_EXAMINE): Make this a
macro instead of an inline function,
(MSG_EXAMINE): Likewise.
* hurd/hurd/ioctl.h (_HURD_HANDLE_IOCTLS_1): Remove extraneous ##.
* hurd/get-host.c: Include <string.h> for decls of built-ins.
* hurd/hurdchdir.c: Likewise.
* sysdeps/mach/hurd/i386/sigreturn.c: Likweise.
* sysdeps/mach/hurd/opendir.c: Likewise.
* mach/mach_init.c: Include <unistd.h> for _exit decl.
* mach/errsystems.awk: Give output file a trailing newline.
* mach/Machrules (MIG): Prepend CC='${CC}' to the mig command, so that
the script will use our compiler for the cpp stage.
With --enable-all-warnings we get a whole bunch of warnings,
and these are just a few fixes; there are more needed to silence it.
* mach/mach/mig_support.h (__mig_strncpy, mig_strncpy): Add extern
decls before extern inline defns to quiet gcc warning.
* hurd/hurd/threadvar.h (__hurd_threadvar_location_from_sp): Likewise.
* sysdeps/mach/i386/machine-sp.h (__thread_stack_pointer): Likewise.
* sysdeps/mach/hurd/i386/intr-msg.h (INTR_MSG_TRAP): Mark OPTION and
TIMEOUT as outputs of the asm to indicate that the signal thread
might mutate them.
* hurd/intr-msg.c (_hurd_intr_rpc_mach_msg): Short circuit to plain
mach_msg if only sending or only receiving (i.e., not an RPC). When
making an RPC that might get interrupted, save OPTION and the portion
of the message buffer that gets clobbered by an EINTR reply message,
and properly restore them before attempting to retry the request
message send.
* hurd/hurdmsg.c (_S_msg_report_wait): Function removed.
* hurd/report-wait.c: New file.
* hurd/Makefile (routines): Added report-wait.
* sysdeps/mach/hurd/Makefile (inhibit-unix-syscalls): New variable.
* sysdeps/mach/hurd/i386/intr-msg.h (struct mach_msg_trap_args):
New type.
(SYSCALL_EXAMINE, MSG_EXAMINE): New inline functions.
* sysdeps/mach/hurd/i386/trampoline.c (struct mach_msg_trap_args):
Structure moved to intr-msg.h; include that.
* time/Makefile (CFLAGS-ialloc.c): Add -Wno-unused.
(CFLAGS-scheck.c): New variable.
* sysdeps/mach/hurd/dl-sysdep.c (__hurd_sigthread_stack_base,
__hurd_sigthread_stack_end, __hurd_sigthread_variables,
__hurd_threadvar_stack_mask): New variables.
* sysdeps/mach/hurd/fork.c: Set the new task's exception port to
its new message port.
* misc/init-misc.c: Put __init_misc in the __libc_subinit set.
* configure.in (uname): Add quoting.
* sysdeps/mach/hurd/fchdir.c: Don't consult errno unless lookup fails.
* hurd/fchroot.c: Likewise.
* posix/sys/types.h [GCC >= 2.7]: Define intN_t/u_intN_t using
__attribute__ ((__mode__ (__XX__))).
Wed Feb 7 03:24:05 1996 Torbjorn Granlund <tege@tmg.se>
* sysdeps/i386/i586/memcopy.h (WORD_COPY_FWD): Manually allocate
destination cache lines.
(WORD_COPY_BWD): Likewise.
Wed Feb 7 14:16:36 1996 Roland McGrath <roland@churchy.gnu.ai.mit.edu>
* sysdeps/generic/Makefile (make_siglist): Get signum.h absolute
file name first thing, before $(native-compile) changes directories.
From Gord Matzigkeit <gord@enci.ucalgary.ca>:
* sysdeps/unix/make_errlist.c: Use strerror if available.
* sysdeps/unix/configure.in: New file
* sysdeps/unix/bsd/sun/syscalls.list: Added sigvec.
* sysdeps/unix/bsd/sun/sigvec.S: File removed.
* sysdeps/stub/sendto.c: Make sockaddr arg pointer to const.
* sysdeps/stub/connect.c: Likewise.
* sysdeps/stub/bind.c: Likewise.
* hurd/hurdlookup.c (__hurd_file_name_lookup_retry): RETRYNAME of
"" is only special for FS_RETRY_NORMAL; for FS_RETRY_REAUTH, do
another dir_lookup of "".
* inet/netdb.h: Moved to resolv.
* inet/Makefile (headers): Remove netdb.h.
* resolv/Makefile (headers): Add netdb.h.
* resolv/gethnamaddr.c, resolv/inet_addr.c, resolv/netdb.h,
resolv/res_send.c: Updated from BIND-4.9.3-BETA26.
* hurd/thread-cancel.c: If SS->cancel_hook is not null, call it before
resuming the thread.
* hurd/hurd/signal.h (struct hurd_sigstate): New member `cancel_hook'.
* hurd/Makefile: Removed dep on hurd/signal.h for RPC stub objects.
Mon Aug 21 16:37:09 1995 Roland McGrath <roland@churchy.gnu.ai.mit.edu>
* sysdeps/i386/dl-machine.h (elf_machine_rel): Grok R_386_NONE
relocs, and do nothing. Why the linker generates them we may
never know.
* sysdeps/mach/hurd/i386/intr-msg.h: New file.
