well-known race condition, which elimination was the reason for the
function appearance in first place. If sigmask supplied as argument to
pselect() enables a signal, the signal might be delivered before thread
called select(2), causing lost wakeup. Reimplement pselect() in kernel,
making change of sigmask and sleep atomic.
Since signal shall be delivered to the usermode, but sigmask restored,
set TDP_OLDMASK and save old mask in td_oldsigmask. The TDP_OLDMASK
should be cleared by ast() in case signal was not gelivered during
syscall execution.
Reviewed by: davidxu
Tested by: pho
MFC after: 1 month
while in kernel mode, and later changing signal mask to block the
signal, was fixed for sigprocmask(2) and ptread_exit(3). The same race
exists for sigreturn(2), setcontext(2) and swapcontext(2) syscalls.
Use kern_sigprocmask() instead of direct manipulation of td_sigmask to
reschedule newly blocked signals, closing the race.
Reviewed by: davidxu
Tested by: pho
MFC after: 1 month
kern_sigprocmask() to properly notify other possible candidate threads
for signal delivery.
Since sigsuspend() shall only return to usermode after a signal was
delivered, do cursig/postsig loop immediately after waiting for
signal, repeating the wait if wakeup was spurious due to race with
other thread fetching signal from the process queue before us. Add
thread_suspend_check() call to allow the thread to be stopped or killed
while in loop.
Modify last argument of kern_sigprocmask() from boolean to flags,
allowing the function to be called with locked proc. Convertion of the
callers that supplied 1 to the old argument will be done in the next
commit, and due to SIGPROCMASK_OLD value equial to 1, code is formally
correct in between.
Reviewed by: davidxu
Tested by: pho
MFC after: 1 month
no matter whether we are compiled as module or if our default of the
net.inet6.ip6.v6only sysctl already matches what we would set.
This avoids unnecessary complications with modules, VIMAGES, INET6 and
the sysctl value, especially considering that most users will use
linux compat as a module.
Discussed with: kib, rwatson (weeks ago)
Reviewed by: rwatson
MFC after: 6 weeks
- Do not map entire real mode memory (1MB). Instead, we map IVT/BDA and
ROM area separately. Most notably, ROM area is mapped as device memory
(uncacheable) as it should be. User memory is dynamically allocated and
free'ed with contigmalloc(9) and contigfree(9). Remove now redundant and
potentially dangerous x86bios_alloc.c. If this emulator ever grows to
support non-PC hardware, we may implement it with rman(9) later.
- Move all host-specific initializations from x86emu_util.c to x86bios.c and
remove now unnecessary x86emu_util.c. Currently, non-PC hardware is not
supported. We may use bus_space(9) later when the KPI is fixed.
- Replace all bzero() calls for emulated registers with more obviously named
x86bios_init_regs(). This function also initializes DS and SS properly.
- Add x86bios_get_intr(). This function checks if the interrupt vector is
available for the platform. It is not necessary for PC-compatible hardware
but it may be needed later. ;-)
- Do not try turning off monitor if DPMS does not support the state.
- Allocate stable memory for VESA OEM strings instead of just holding
pointers to them. They may or may not be accessible always. Fix a memory
leak of video mode table while I am here.
- Add (experimental) BIOS POST call for vesa(4). This function calls VGA
BIOS POST code from the current VGA option ROM. Some video controllers
cannot save and restore the state properly even if it is claimed to be
supported. Usually the symptom is blank display after resuming from suspend
state. If the video mode does not match the previous mode after restoring,
we try BIOS POST and force the known good initial state. Some magic was
taken from NetBSD (and it was taken from vbetool, I believe.)
- Add a loader tunable for vgapci(4) to give a hint to dpms(4) and vesa(4)
to identify who owns the VESA BIOS. This is very useful for multi-display
adapter setup. By default, the POST video controller is automatically
probed and the tunable "hw.pci.default_vgapci_unit" is set to corresponding
vgapci unit number. You may override it from loader but it is very unlikely
to be necessary. Unfortunately only AGP/PCI/PCI-E controllers can be
matched because ISA controller does not have necessary device IDs.
- Fix a long standing bug in state save/restore function. The state buffer
pointer should be ES:BX, not ES:DI according to VBE 3.0. If it ever worked,
that's because BX was always zero. :-)
- Clean up register initializations more clearer per VBE 3.0.
- Fix a lot of style issues with vesa(4).
first and the native ia32 compat as middle (before other things).
o(ld)brandinfo as well as third party like linux, kfreebsd, etc.
stays on SI_ORDER_ANY coming last.
The reason for this is only to make sure that even in case we would
overflow the MAX_BRANDS sized array, the native FreeBSD brandinfo
would still be there and the system would be operational.
Reviewed by: kib
MFC after: 1 month
- Remove CS and IP registers from x86bios.h. They have no use for us.
- Adjust register dump to make it little bit more useful for debugging.
Submitted by: paradox (ddkprog yahoo com)[1] (initial version)
FreeBSD 8, the compatibility shims should be built not just when FreeBSD 7
compatibility is requested, but also when compatibility with any older
FreeBSD version where that feature was present is requested.o
Without this patch, a kernel config that sets COMPAT_FREEBSD6 but not *7
would fail to build due to inconsistencies between the declaration of the
compatibility shims and their use in the SysV code.
There are similar errors in other *proto.h headers in the tree.
MFC after: 3 weeks
longs. Since 32bit processes longs are 4 bytes, 64bit kernel may copy in
or out 4 bytes more then the process expected.
Calculate the amount of bytes to copy taking into account size of fd_set
for the current process ABI.
Diagnosed and tested by: Peter Jeremy <peterjeremy acm org>
Reviewed by: jhb
MFC after: 1 week
correctly and do not match a colliding Debian GNU/kFreeBSD
brandinfo statements.
For this mark the Debian GNU/kFreeBSD brandinfo that it must have
an .note.ABI-tag section and ignore the old EI_OSABI brandinfo
when comparing a possibly colliding set of options.
Due to SYSINIT we add the brandinfo in a non-deterministic order,
so native FreeBSD is not always first. We may want to consider
to force native FreeBSD to come first as well.
The only way a problem could currently be noticed is when running an
i386 binary without the .note.ABI-tag on amd64 and the Debian GNU/kFreeBSD
brandinfo was matched first, as the fallback to ld-elf32.so.1 does
not exist in that case.
Reported and tested by: ticso
In collaboration with: kib
MFC after: 3 days
Handle GNU/Linux according to LSB Core Specification 4.0,
Chapter 11. Object Format, 11.8. ABI note tag.
Also check the first word of desc, not only name, according to
glibc abi-tags specification to distinguish between Linux and
kFreeBSD.
Add explicit handling for Debian GNU/kFreeBSD, which runs
on our kernels as well [2].
In {amd64,i386}/trap.c, when checking osrel of the current process,
also check the ABI to not change the signal behaviour for Linux
binary processes, now that we save an osrel version for all three
from the lists above in struct proc [2].
These changes make it possible to run FreeBSD, Debian GNU/kFreeBSD
and Linux binaries on the same machine again for at least i386 and
amd64, and no longer break kFreeBSD which was detected as GNU(/Linux).
PR: kern/135468
Submitted by: dchagin [1] (initial patch)
Suggested by: kib [2]
Tested by: Petr Salinger (Petr.Salinger seznam.cz) for kFreeBSD
Reviewed by: kib
MFC after: 3 days
several critical bugs, including race conditions and lock order issues:
Replace the single rwlock, ifnet_lock, with two locks, an rwlock and an
sxlock. Either can be held to stablize the lists and indexes, but both
are required to write. This allows the list to be held stable in both
network interrupt contexts and sleepable user threads across sleeping
memory allocations or device driver interactions. As before, writes to
the interface list must occur from sleepable contexts.
Reviewed by: bz, julian
MFC after: 3 days
vnet.h, we now use jails (rather than vimages) as the abstraction
for virtualization management, and what remained was specific to
virtual network stacks. Minor cleanups are done in the process,
and comments updated to reflect these changes.
Reviewed by: bz
Approved by: re (vimage blanket)
old ABI versions of the relevant control system call (e.g.
freebsd7_freebsd32_msgctl() instead of freebsd32_msgctl() for msgsys()).
Approved by: re (kib)
restrictions) were found to be inadequately described by a boolean.
Define a new parameter type with three values (disable, new, inherit)
to handle these and future cases.
Approved by: re (kib), bz (mentor)
Discussed with: rwatson
(DPCPU), as suggested by Peter Wemm, and implement a new per-virtual
network stack memory allocator. Modify vnet to use the allocator
instead of monolithic global container structures (vinet, ...). This
change solves many binary compatibility problems associated with
VIMAGE, and restores ELF symbols for virtualized global variables.
Each virtualized global variable exists as a "reference copy", and also
once per virtual network stack. Virtualized global variables are
tagged at compile-time, placing the in a special linker set, which is
loaded into a contiguous region of kernel memory. Virtualized global
variables in the base kernel are linked as normal, but those in modules
are copied and relocated to a reserved portion of the kernel's vnet
region with the help of a the kernel linker.
Virtualized global variables exist in per-vnet memory set up when the
network stack instance is created, and are initialized statically from
the reference copy. Run-time access occurs via an accessor macro, which
converts from the current vnet and requested symbol to a per-vnet
address. When "options VIMAGE" is not compiled into the kernel, normal
global ELF symbols will be used instead and indirection is avoided.
This change restores static initialization for network stack global
variables, restores support for non-global symbols and types, eliminates
the need for many subsystem constructors, eliminates large per-subsystem
structures that caused many binary compatibility issues both for
monitoring applications (netstat) and kernel modules, removes the
per-function INIT_VNET_*() macros throughout the stack, eliminates the
need for vnet_symmap ksym(2) munging, and eliminates duplicate
definitions of virtualized globals under VIMAGE_GLOBALS.
Bump __FreeBSD_version and update UPDATING.
Portions submitted by: bz
Reviewed by: bz, zec
Discussed with: gnn, jamie, jeff, jhb, julian, sam
Suggested by: peter
Approved by: re (kensmith)
if the new file mode is the same as it was before; however, this
optimization must be disabled for filesystems that support NFSv4 ACLs.
Chmod uses pathconf(2) to determine whether this is the case - however,
pathconf(2) always follows symbolic links, while the 'chmod -h' doesn't.
This change adds lpathconf(3) to make it possible to solve that problem
in a clean way.
Reviewed by: rwatson (earlier version)
Approved by: re (kib)
specific macros for each audit argument type. This makes it easier to
follow call-graphs, especially for automated analysis tools (such as
fxr).
In MFC, we should leave the existing AUDIT_ARG() macros as they may be
used by third-party kernel modules.
Suggested by: brooks
Approved by: re (kib)
Obtained from: TrustedBSD Project
MFC after: 1 week
- The uid/cuid members of struct ipc_perm are now uid_t instead of unsigned
short.
- The gid/cgid members of struct ipc_perm are now gid_t instead of unsigned
short.
- The mode member of struct ipc_perm is now mode_t instead of unsigned short
(this is merely a style bug).
- The rather dubious padding fields for ABI compat with SV/I386 have been
removed from struct msqid_ds and struct semid_ds.
- The shm_segsz member of struct shmid_ds is now a size_t instead of an
int. This removes the need for the shm_bsegsz member in struct
shmid_kernel and should allow for complete support of SYSV SHM regions
>= 2GB.
- The shm_nattch member of struct shmid_ds is now an int instead of a
short.
- The shm_internal member of struct shmid_ds is now gone. The internal
VM object pointer for SHM regions has been moved into struct
shmid_kernel.
- The existing __semctl(), msgctl(), and shmctl() system call entries are
now marked COMPAT7 and new versions of those system calls which support
the new ABI are now present.
- The new system calls are assigned to the FBSD-1.1 version in libc. The
FBSD-1.0 symbols in libc now refer to the old COMPAT7 system calls.
- A simplistic framework for tagging system calls with compatibility
symbol versions has been added to libc. Version tags are added to
system calls by adding an appropriate __sym_compat() entry to
src/lib/libc/incldue/compat.h. [1]
PR: kern/16195 kern/113218 bin/129855
Reviewed by: arch@, rwatson
Discussed with: kan, kib [1]
NGROUPS_MAX, eliminate ABI dependencies on them, and raise the to 1024
and 1023 respectively. (Previously they were equal, but under a close
reading of POSIX, NGROUPS_MAX was defined to be too large by 1 since it
is the number of supplemental groups, not total number of groups.)
The bulk of the change consists of converting the struct ucred member
cr_groups from a static array to a pointer. Do the equivalent in
kinfo_proc.
Introduce new interfaces crcopysafe() and crsetgroups() for duplicating
a process credential before modifying it and for setting group lists
respectively. Both interfaces take care for the details of allocating
groups array. crsetgroups() takes care of truncating the group list
to the current maximum (NGROUPS) if necessary. In the future,
crsetgroups() may be responsible for insuring invariants such as sorting
the supplemental groups to allow groupmember() to be implemented as a
binary search.
Because we can not change struct xucred without breaking application
ABIs, we leave it alone and introduce a new XU_NGROUPS value which is
always 16 and is to be used or NGRPS as appropriate for things such as
NFS which need to use no more than 16 groups. When feasible, truncate
the group list rather than generating an error.
Minor changes:
- Reduce the number of hand rolled versions of groupmember().
- Do not assign to both cr_gid and cr_groups[0].
- Modify ipfw to cache ucreds instead of part of their contents since
they are immutable once referenced by more than one entity.
Submitted by: Isilon Systems (initial implementation)
X-MFC after: never
PR: bin/113398 kern/133867
in the type field of system call tables. Specifically, one can now use
the 'NO*' types as flags in addition to the 'COMPAT*' types. For example,
to tag 'COMPAT*' system calls as living in a KLD via NOSTD. The COMPAT*
type is required to be listed first in this case.
- Add new functions 'type()' and 'flag()' to the embedded awk script in
makesyscalls.sh that return true if a requested flag is found in the
type field ($3). The flag() function checks all of the flags in the
field, but type() only checks the first flag. type() is meant to be
used in the top-level "switch" statement and flag() should be used
otherwise.
- Retire the CPT_NOA type, it is now replaced with "COMPAT|NOARGS" using
the flags approach.
- Tweak the comment descriptions of COMPAT[46] system calls so that they
say "freebsd[46] foo" rather than "old foo".
- Document the COMPAT6 type.
- Sync comments in compat32 syscall table with the master table.
any open file descriptors >= 'lowfd'. It is largely identical to the same
function on other operating systems such as Solaris, DFly, NetBSD, and
OpenBSD. One difference from other *BSD is that this closefrom() does not
fail with any errors. In practice, while the manpages for NetBSD and
OpenBSD claim that they return EINTR, they ignore internal errors from
close() and never return EINTR. DFly does return EINTR, but for the common
use case (closing fd's prior to execve()), the caller really wants all
fd's closed and returning EINTR just forces callers to call closefrom() in
a loop until it stops failing.
Note that this implementation of closefrom(2) does not make any effort to
resolve userland races with open(2) in other threads. As such, it is not
multithread safe.
Submitted by: rwatson (initial version)
Reviewed by: rwatson
MFC after: 2 weeks
