On i386, Clang complains about misaligned atomic operations. Silence
these warnings to fix the build on FreeBSD/i386.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Alan Somers <asomers@gmail.com>
Sponsored by: ConnectWise
Closes#17708
Traditionally, unused dentries would be cached in the dentry cache until
the associated entry is no longer on disk. The cached dentry continues
to hold an inode reference, causing the inode to be pinned (see previous
commit).
Here we implement the dentry op d_delete, which is roughly analogous to
the drop_inode superblock op, and add a zfs_delete_dentry tunable to
control its behaviour. By default it continues the traditional
behaviour, but when the tunable is enabled, we signal that an unused
dentry should be freed immediately, releasing its inode reference, and
so allowing that inode to be deleted if no longer in use.
Sponsored-by: Klara, Inc.
Sponsored-by: Fastmail Pty Ltd
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <alexander.motin@TrueNAS.com>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes#17746
Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Paul Dagnelie <paul.dagnelie@klarasystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes#17747
We only have extremely narrow uses, so move it all into a single
function that does only what we need, with and without d_set_d_op().
Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#17621
Accidentally removed calls in ed048fdc5b.
Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#17621
If ARCH environment variable is set it can cause the failure of the
kernel modules check during the configure step. The resulting error
will be confusing, and may looks like this:
> checking for kernel config option compatibility... done
> checking whether CONFIG_MODULES is defined... no
> configure: error:
> *** This kernel does not include the required loadable module
> *** support!
Detect when ARCH is print a warning.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Maksym Shkolnyi <maksym.shkolnyi@workato.com>
Closes#17680
LLVM-21 enables -Wuninitialized-const-pointer which results in the
following compiler warning and the bdev_file_open_by_path() interface
not being detected for 6.9 and newer kernels. The blk_holder_ops
are not used by the ZFS code so we can safely use a NULL argument
for this check.
bdev_file_open_by_path/bdev_file_open_by_path.c:110:54: error:
variable 'h' is uninitialized when passed as a const pointer
argument here [-Werror,-Wuninitialized-const-pointer]
Reviewed-by: Rob Norris <robn@despairlabs.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#17682Closes#17684
glibc includes linux/stat.h for statx, but musl defines its own statx
struct and associated constants, which does not include STATX_MNT_ID
yet. Thus, including linux/stat.h directly should be avoided for
maximum libc compatibility.
Tested on:
- glibc: x86_64, i686, aarch64, armv7l, armv6l
- musl: x86_64, aarch64, armv7l, armv6l
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Tested-By: Achill Gilgenast <achill@achill.org>
Signed-off-by: classabbyamp <dev@placeviolette.net>
Closes#17675
If $KERNEL_CC was not defined, configure status output would print an
empty string where the kernel compiler should have been. Fix this and
simplify the code generally.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ivan Shapovalov <intelfx@intelfx.name>
Closes#16997
Output the result of the "iops->mkdir() returns struct dentry*"
check to cleanup the configure output.
Reviewed-by: Alexander Motin <alexander.motin@TrueNAS.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#17641
This uses the AVX2 versions of the AESENC and PCLMULQDQ instructions; on
Zen 3 this provides an up to 80% performance improvement.
Original source:
d5440dd2c2/gen/bcm/aes-gcm-avx2-x86_64-linux.S
See the original BoringSSL commit at
3b6e1be439.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Rob Norris <robn@despairlabs.com>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Attila Fülöp <attila@fueloep.org>
Signed-off-by: Joel Low <joel@joelsplace.sg>
Closes#17058
Be standard-compliant by using `int main()`.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <alexander.motin@TrueNAS.com>
Signed-off-by: Attila Fülöp <attila@fueloep.org>
Closes#13303Closes#17590
On Linux, when doing path lookup with LOOKUP_RCU, dentry and inode can
be dereferenced without refcounts and locks. For this reason, dentry and
inode must only be freed after RCU grace period.
However, zfs currently frees inode in zfs_inode_destroy synchronously
and we can't use GPL-only call_rcu() in zfs directly. Fortunately, on
Linux 5.2 and after, if we define sops->free_inode(), the kernel will do
call_rcu() for us.
This issue may be triggered more easily with init_on_free=1 boot
parameter:
BUG: kernel NULL pointer dereference, address: 0000000000000020
RIP: 0010:selinux_inode_permission+0x10e/0x1c0
Call Trace:
? show_trace_log_lvl+0x1be/0x2d9
? show_trace_log_lvl+0x1be/0x2d9
? show_trace_log_lvl+0x1be/0x2d9
? security_inode_permission+0x37/0x60
? __die_body.cold+0x8/0xd
? no_context+0x113/0x220
? exc_page_fault+0x6d/0x130
? asm_exc_page_fault+0x1e/0x30
? selinux_inode_permission+0x10e/0x1c0
security_inode_permission+0x37/0x60
link_path_walk.part.0.constprop.0+0xb5/0x360
? path_init+0x27d/0x3c0
path_lookupat+0x3e/0x1a0
filename_lookup+0xc0/0x1d0
? __check_object_size.part.0+0x123/0x150
? strncpy_from_user+0x4e/0x130
? getname_flags.part.0+0x4b/0x1c0
vfs_statx+0x72/0x120
? ioctl_has_perm.constprop.0.isra.0+0xbd/0x120
__do_sys_newlstat+0x39/0x70
? __x64_sys_ioctl+0x8d/0xd0
do_syscall_64+0x30/0x40
entry_SYSCALL_64_after_hwframe+0x62/0xc7
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Rob Norris <rob.norris@klarasystems.com>
Signed-off-by: Chunwei Chen <david.chen@nutanix.com>
Co-authored-by: Chunwei Chen <david.chen@nutanix.com>
Closes#17546
Use statx to verify that path-based unmounts proceed only if the
mountpoint reported by statx matches the MNTTAB entry reported by
libzfs, aborting the operation if they differ. Align
`zfs umount /path` behavior with `zfs umount dataset`.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Ameer Hamza <ahamza@ixsystems.com>
Closes#17481
Fixes an obvious typo, where a variable was missing the required
leading dollar sign ($)
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Martin Rüegg <martin.rueegg@metaworx.ch>
Closes#17480
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#17443
Linux 5.16 by default fails the build on objtool warnings. We have
known and understood objtool warnings we can't fix without
involving Linux maintainers.
To work around this we introduce an objtool wrapper script which
removes the `--Werror` flag.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Attila Fülöp <attila@fueloep.org>
Closes#17456
If the kernel will honour our error returns, use them. If not, fool it
by setting a writeback error on the superblock, if available.
Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Paul Dagnelie <paul.dagnelie@klarasystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes#17420
After #17401 the Linux build produces some stack related warnings.
Silence them with the `STACK_FRAME_NON_STANDARD` macro.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Signed-off-by: Attila Fülöp <attila@fueloep.org>
Co-authored-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#17410
5b9e695 added specific userspace versions of abd_os.h and abd_impl_os.h
for libzpool. However, abd.h and abd_impl.h, which include them, are
packaged with libzfs, so other programs building against libzfs can
fail to build, either because the headers aren't installed, or because
they aren't on any standard include path.
So, move abd_os.h and abd_impl_os.h to libspl, where they we will be
installed alongside abd.h and abd_impl.h in a known path.
Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes#16940Closes#17390Closes#17394
Renamed in 6.2, and the compat wrapper removed in 6.15. No signature or
functional change apart from that, so a very minimal update for us.
Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Pavel Snajdr <snajpa@snajpa.net>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#17229
The intent is that the filesystem may have a reference to an "old"
version of the new directory, eg if it was keeping it alive because a
remote NFS client still had it open.
We don't need anything like that, so this really just changes things so
we return error codes encoded in pointers.
Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Pavel Snajdr <snajpa@snajpa.net>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#17229
This commit adds support for using llvm-libunwind for kernels built
using llvm and clang. The two differences are that the largest register
index is given by _LIBUNWIND_HIGHEST_DWARF_REGISTER, we need to check
whether the register is a floating point register and the prototype
for unw_regname takes the unwind cursor as the first argument.
Reviewed-by: Rob Norris <robn@despairlabs.com>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Sebastian Pauka <me@spauka.se>
Closes#17230
The tiniest typo in dd2a46b5e6 (#17106) broke it, by setting the wrong
var with the test var, resulting in it always producing "no".
Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed by: Attila Fülöp <attila@fueloep.org>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#17236
The 6.0 kernel removes the 'migratepage' VFS op. Check for
migratepage.
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Rob Norris <robn@despairlabs.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org
Kernel checks are the heaviest part of the configure checks. This allows
the results to be cached through the normal autoconf cache.
Since we don't want to reuse cached values for different kernels, but
don't want to discard the entire cache on every kernel, we instead add a
short checksum to kernel config cache keys, based on the version and
path, so the cache can hold results for multiple different kernels.
Sponsored-by: https://despairlabs.com/sponsor/
Signed-off-by: Rob Norris <robn@despairlabs.com>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
It turns out that approach taken in the original version of the patch
was wrong. So now, we're taking approach in-line with how kernel
actually does it - when sb is being torn down, access to it
is serialized via sb->s_umount rwsem, only when that lock is taken
is it okay to work with s_flags - and the other mistake I was doing
was trying to make SB_ACTIVE work, but apparently the kernel checks
the negative variant - not SB_DYING and not SB_BORN.
Kernels pre-6.6 don't have SB_DYING, but check if sb is hashed
instead.
Signed-off-by: Pavel Snajdr <snajpa@snajpa.net>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Sponsored-by: https://despairlabs.com/sponsor/
Signed-off-by: Rob Norris <robn@despairlabs.com>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
This is a convenience for filesystems that need the inode of their
parent or their own name, as its often complicated to get that
information. We don't need those things, so this is just detecting which
prototype is expected and adjusting our callback to match.
Sponsored-by: https://despairlabs.com/sponsor/
Signed-off-by: Rob Norris <robn@despairlabs.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Originally #16856 updated Linux Direct I/O requests to use the new
pin_user_pages API. However, it was an oversight that this PR only
handled iov_iter's of type ITER_IOVEC and ITER_UBUF. Other iov_iter
types may try and use the pin_user_pages API if it is available. This
can lead to panics as the iov_iter is not being iterated over correctly
in zfs_uio_pin_user_pages().
Unfortunately, generic iov_iter API's that call pin_user_page_fast() are
protected as GPL only. Rather than update zfs_uio_pin_user_pages() to
account for all iov_iter types, we can simply just call
zfs_uio_get_dio_page_iov_iter() if the iov_iter type is not ITER_IOVEC
or ITER_UBUF. zfs_uio_get_dio_page_iov_iter() calls the
iov_iter_get_pages() calls that can handle any iov_iter type.
In the future it might be worth using the exposed iov_iter iterator
functions that are included in the header iov_iter.h since v6.7. These
functions allow for any iov_iter type to be iterated over and advanced
while applying a step function during iteration. This could possibly be
leveraged in zfs_uio_pin_user_pages().
A new ZFS test case was added to test that a ITER_BVEC is handled
correctly using this new code path. This test case was provided though
issue #16956.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ameer Hamza <ahamza@ixsystems.com>
Signed-off-by: Brian Atkinson <batkinson@lanl.gov>
Closes#16956Closes#17006
In order to correctly cross-compile, one has to pass ARCH and
CROSS_COMPILE make flags to kernel module build calls. Facilitate this
in the same way as for custom CC flag by recognizing KERNEL_-prefixed
configure environment variables of same name.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Phil Sutter <phil@nwl.cc>
Closes#16924
#15793 wanted to make zfs_strerror threadsafe, unfortunately, it
turned out that strerror_l() usage was wrong, and also, some libc
implementations dont have strerror_l().
zfs_strerror() now simply calls original strerror() and copies the
result to a thread-local buffer, then returns that.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Richard Kojedzinszky <richard@kojedz.in>
Closes#15793Closes#16640Closes#16923
As of kernel v5.8, pin_user_pages* interfaced were introduced. These
interfaces use the FOLL_PIN flag. This is preferred interface now for
Direct I/O requests in the kernel. The reasoning for using this new
interface for Direct I/O requests is explained in the kernel
documenetation:
Documentation/core-api/pin_user_pages.rst
If pin_user_pages_unlocked is available, the all Direct I/O requests
will use this new API to stay uptodate with the kernel API requirements.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Brian Atkinson <batkinson@lanl.gov>
Closes#16856
There were checks still in place to verify we could completely use
iov_iter's on the Linux side. All interfaces are available as of kernel
4.18, so there is no reason to check whether we should use that
interface at this point. This PR completely removes the UIO_USERSPACE
type. It also removes the check for the direct_IO interface checks.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Brian Atkinson <batkinson@lanl.gov>
Closes#16856
This is purely a cosmetic fix which removes a stray "no" from
the configure output.
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#16867
Adjust the m4 function to mimic sentinel we use in spl-proc.c
This fixes the detection on kernels compiled with CONFIG_RANDSTRUCT=y
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Rob Norris <robn@despairlabs.com>
Reviewed-by: Pavel Snajdr <snajpa@snajpa.net>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Ivan Volosyuk <Ivan.Volosyuk@gmail.com>
Closes: #16620Closes: #16805
Avoids using fallback_migrate_folio, which starts unnecessary writeback
(leading to BUG in migrate_folio_extra).
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: tstabrawa <59430211+tstabrawa@users.noreply.github.com>
Closes#16568Closes#16723
This reverts commit b052035990.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: tstabrawa <59430211+tstabrawa@users.noreply.github.com>
Closes#16568Closes#16723
Before 4.20, kernel_siginfo_t was just called siginfo_t. This was
causing the kthread_dequeue_signal_3arg_task check, which uses
kernel_siginfo_t, to fail on older kernels.
In d6b8c17f1, we started checking for the "new" three-arg
dequeue_signal() by testing for the "old" version. Because that test is
explicitly using kernel_siginfo_t, it would fail, leading to the build
trying to use the new three-arg version, which would then not compile.
This commit fixes that by avoiding checking for the old 3-arg
dequeue_signal entirely. Instead, we check for the new one, as well as
the 4-arg form, and we use the old form as a fallback. This way, we
never have to test for it explicitly, and once we're building
HAVE_SIGINFO will make sure we get the right kernel_siginfo_t for it, so
everything works out nice.
Original-patch-by: Finix <yancw@info2soft.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#16666
Some C libraries, such as uClibc, do not provide strerror_l() in
which case we fallback to strerror().
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#16636Closes#16640
.NOTPARALLEL target is being forced on userspace as well. This commit
removes .NOTPARALEL target and only serializes the execution of
native-deb* targets.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Umer Saleem <usaleem@ixsystems.com>
Closes#16622
The ABI of libzfs and libzpool have breaking changes since last
SONAME bump in commit fe6babc:
* libzfs: `zpool_print_unsup_feat` removed (used by zpool cmd).
* libzpool: multiple `ddt_*` symbols removed (used by zdb cmd).
Bump them to avoid ABI breakage.
See: https://github.com/openzfs/zfs/pull/11817
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Shengqi Chen <harry-chen@outlook.com>
Closes#16609
Running native-deb* targets in parallel via make is not supported.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Umer Saleem <usaleem@ixsystems.com>
Closes#14736
torvalds/linux@09022bc196 removes the flag, and the corresponding
SetPageError() and ClearPageError() macros, with no replacement offered.
Going back through the upstream history, use of this flag has been
gradually removed over the last year as part of the long tail of
converting everything to folios. Interesting tidbit comments from
torvalds/linux@29e9412b25 and torvalds/linux@420e05d0de suggest that
this flag has not been used meaningfully since page writeback failures
started being recorded in errseq_t instead (the whole "fsyncgate" thing,
~2017, around torvalds/linux@8ed1e46aaf).
Given that, it's possible that since perhaps Linux 4.13 we haven't been
getting anything by setting the flag. I don't know if that's true and/or
if there's something we should be doing instead, but my gut feel is that
its probably fine we only use the page cache as a proxy to allow mmap()
to work, rather than backing IO with it.
As such, I'm expecting that removing this will do no harm, but I'm
leaving it in for older kernels to maintain status quo, and if there is
an overall better way, that is left for a future change.
Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#16582
linux/torvalds@11068e0b64 removes it, suggesting this was a always
there as a helper to handle concurrent seeks, which all filesystems now
handle themselves if necessary.
Without looking into the mechanism, I can imagine how it might have been
used, but we have always set it to zero and never read from it,
presumably because we've always tracked per-caller position through the
znode anyway. So I don't see how there can be any functional change for
us by removing it. I've stayed conservative though and left it in for
older kernels, since its clearly not hurting anything there.
Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#16582
See torvalds/linux@a2b80ce87a. It claims the task arg is always
`current`, and so it is with us, so this is a safe change to make. The
only spanner is that we also support the older pre-5.17 3-arg
dequeue_signal() which had different meaning, so we have to check the
types to get the right one.
Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#16582
Linux page migration code won't wait for writeback to complete unless
it needs to call release_folio. Call SetPagePrivate wherever
PageUptodate is set and define .release_folio, to cause
fallback_migrate_folio to wait for us.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: tstabrawa <59430211+tstabrawa@users.noreply.github.com>
Closes#15140Closes#16568
META lists the maximum kernel version we consider to be fully supported.
However, we don't enforce this.
Sometimes we ship experimental patches for a newer kernel than we're
ready to support or, less often, we compile just fine against a newer
kernel. Invariably, something doesn't quite work properly, and it's
difficult for users to understand that they're actually running against
a kernel that we're not yet ready to support.
This commit tries to improve this situation. First, it simply enforces
Linux-Maximum, by having configure bail out if you try to compile
against a newer version that.
Then, it adds the --enable-linux-experimental switch to configure. When
supplied, this disables enforcing the maximum version, allowing the user
to attempt to build against a kernel with version higher than
Linux-Maximum.
Finally, if the switch is supplied _and_ configure is run against a
higher kernel version, it shows a big warning message when configure
finishes, and defines HAVE_LINUX_EXPERIMENTAL for the build. This allows
us to add code to modify runtime behaviour as well.
Reviewed-by: Robert Evans <evansr@google.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Sponsored-by: https://despairlabs.com/sponsor/Closes#15986
