All callers pass a 0 limit to xfs_rtfind_back, so remove the argument
and hard code it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Turn the ISVALID macro defined and used inside in xfs_bmap_adjacent
that relies on implict context into a proper inline function.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
After going great length to calculate the transaction reservation for
the new geometry, we should also use it to allocate the transaction it
was calculated for.
Fixes: 578bd4ce71 ("xfs: recompute growfsrtfree transaction reservation while growing rt volume")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Currently the RT mount code simply ignores an allocation failure for the
rsum_cache. The code mostly works fine with it, but not having it leads
to nasty corner cases in the growfs code that we don't really handle
well. Switch to failing the mount if we can't allocate the memory, the
file system would not exactly be useful in such a constrained environment
to start with.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Split the RT geometry validation in the early mount code into a
helper than can be reused by repair (from which this code was
apparently originally stolen anyway).
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
[djwong: u64 return value for calc_rbmblocks]
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Replace xfs_validate_rtextents with an open coded check for 0
rtextents. The name for the function implies it does a lot more
than a zero check, which is more obvious when open coded.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Add support for Adreno 306A GPU what is found in MSM8917 SoC.
This GPU marketing name is Adreno 308.
Signed-off-by: Otto Pflüger <otto.pflueger@abscue.de>
[use internal name of the GPU, reword the commit message]
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Barnabás Czémán <trabarni@gmail.com>
Patchwork: https://patchwork.freedesktop.org/patch/605403/
Signed-off-by: Rob Clark <robdclark@chromium.org>
A621 is a clear A662 derivative (same lineage as A650), no explosions
or sick features, other than a NoC bug which can stall the GPU..
Add support for it.
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/611100/
Signed-off-by: Rob Clark <robdclark@chromium.org>
This was apparently never done before.. Program the expected values.
This also gets rid of sneakily setting that register through the HWCG
reg list on A690.
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/611098/
Signed-off-by: Rob Clark <robdclark@chromium.org>
This register's magic value differs wildly between different GPUs, use
the hardcoded data instead of trying to make some logic out of it.
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/611096/
Signed-off-by: Rob Clark <robdclark@chromium.org>
Store the correct values that we happen to have for some A7xx SKUs in
the GPU info struct and fill out the missing information for A6xx GPUs
based on downstream kernel information.
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/611094/
[add missing entry to a615 catalog to resolve conflict]
Signed-off-by: Rob Clark <robdclark@chromium.org>
The if-else monster is so unmaintainable that one case is repeated
twice. Get rid of it.
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/611092/
[add missing entry to a615 catalog to resolve conflict]
Signed-off-by: Rob Clark <robdclark@chromium.org>
A650 family includes A660 family (they've got a big family), A650
itself, and some more A6XX_GEN3 SKUs, all of which should fall into
the same branch of the if-condition. Simplify that.
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/605206/
Signed-off-by: Rob Clark <robdclark@chromium.org>
There is another cause for soft lock-up of GPU in empty ring-buffer:
race between GPU executing last commands and CPU checking ring for
emptiness. On GPU side IRQ for retire is triggered by CACHE_FLUSH_TS
event and RPTR shadow (which is used to check ring emptiness) is updated
a bit later from CP_CONTEXT_SWITCH_YIELD. Thus if GPU is executing its
last commands slow enough or we check that ring too fast we will miss a
chance to trigger switch to lower priority ring because current ring isn't
empty just yet. This can escalate to lock-up situation described in
previous patch.
To work-around this issue we keep track of last submit sequence number
for each ring and compare it with one written to memptrs from GPU during
execution of CACHE_FLUSH_TS event.
Fixes: b1fc2839d2 ("drm/msm: Implement preemption for A5XX targets")
Signed-off-by: Vladimir Lypak <vladimir.lypak@gmail.com>
Patchwork: https://patchwork.freedesktop.org/patch/612047/
Signed-off-by: Rob Clark <robdclark@chromium.org>
On A5XX GPUs when preemption is used it's invietable to enter a soft
lock-up state in which GPU is stuck at empty ring-buffer doing nothing.
This appears as full UI lockup and not detected as GPU hang (because
it's not). This happens due to not triggering preemption when it was
needed. Sometimes this state can be recovered by some new submit but
generally it won't happen because applications are waiting for old
submits to retire.
One of the reasons why this happens is a race between a5xx_submit and
a5xx_preempt_trigger called from IRQ during submit retire. Former thread
updates ring->cur of previously empty and not current ring right after
latter checks it for emptiness. Then both threads can just exit because
for first one preempt_state wasn't NONE yet and for second one all rings
appeared to be empty.
To prevent such situations from happening we need to establish guarantee
for preempt_trigger to make decision after each submit or retire. To
implement this we serialize preemption initiation using spinlock. If
switch is already in progress we need to re-trigger preemption when it
finishes.
Fixes: b1fc2839d2 ("drm/msm: Implement preemption for A5XX targets")
Signed-off-by: Vladimir Lypak <vladimir.lypak@gmail.com>
Patchwork: https://patchwork.freedesktop.org/patch/612045/
Signed-off-by: Rob Clark <robdclark@chromium.org>
Two fields of preempt_record which are used by CP aren't reset on
resume: "data" and "info". This is the reason behind faults which happen
when we try to switch to the ring that was active last before suspend.
In addition those faults can't be recovered from because we use suspend
and resume to do so (keeping values of those fields again).
Fixes: b1fc2839d2 ("drm/msm: Implement preemption for A5XX targets")
Signed-off-by: Vladimir Lypak <vladimir.lypak@gmail.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/612043/
Signed-off-by: Rob Clark <robdclark@chromium.org>
Fine grain preemption (switching from/to points within submits)
requires extra handling in command stream of those submits, especially
when rendering with tiling (using GMEM). However this handling is
missing at this point in mesa (and always was). For this reason we get
random GPU faults and hangs if more than one priority level is used
because local preemption is enabled prior to executing command stream
from submit.
With that said it was ahead of time to enable local preemption by
default considering the fact that even on downstream kernel it is only
enabled if requested via UAPI.
Fixes: a7a4c19c36 ("drm/msm/a5xx: fix setting of the CP_PREEMPT_ENABLE_LOCAL register")
Signed-off-by: Vladimir Lypak <vladimir.lypak@gmail.com>
Patchwork: https://patchwork.freedesktop.org/patch/612041/
Signed-off-by: Rob Clark <robdclark@chromium.org>
There are some cases, such as the one uncovered by Commit 46d4efcccc
("drm/msm/a6xx: Avoid a nullptr dereference when speedbin setting fails")
where
msm_gpu_cleanup() : platform_set_drvdata(gpu->pdev, NULL);
is called on gpu->pdev == NULL, as the GPU device has not been fully
initialized yet.
Turns out that there's more than just the aforementioned path that
causes this to happen (e.g. the case when there's speedbin data in the
catalog, but opp-supported-hw is missing in DT).
Assigning msm_gpu->pdev earlier seems like the least painful solution
to this, therefore do so.
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/602742/
Signed-off-by: Rob Clark <robdclark@chromium.org>
nfsd_pool_stats_open() is used in nfsctl.c, so move it there.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Various functions are only used within the sunrpc module, and several
are only use in the one file. So clean up:
These are marked static, and any EXPORT is removed.
svc_rcpb_setup()
svc_rqst_alloc()
svc_rqst_free() - also moved before first use
svc_rpcbind_set_version()
svc_drop() - also moved to svc.c
These are now not EXPORTed, but are not static.
svc_authenticate()
svc_sock_update_bufs()
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
nlmsvc_timeout always has the same value as (nlm_timeout * HZ), so use
that in the one place that nlmsvc_timeout is used.
In truth it *might* not always be the same as nlmsvc_timeout is only set
when lockd is started while nlm_timeout can be set at anytime via
sysctl. I think this difference it not helpful so removing it is good.
Also remove the test for nlm_timout being 0. This is not possible -
unless a module parameter is used to set the minimum timeout to 0, and
if that happens then it probably should be honoured.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
nfsd4_ssc_init_umount_work() is only used in the nfsd module, so there
is no need to EXPORT it.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
After many rounds of changes in filecache.c, the fix by commit
ce7df055(NFSD: Make the file_delayed_close workqueue UNBOUND)
is gone, now we are getting syslog messages like these:
[ 1618.186688] workqueue: nfsd_file_gc_worker [nfsd] hogged CPU for >13333us 4 times, consider switching to WQ_UNBOUND
[ 1638.661616] workqueue: nfsd_file_gc_worker [nfsd] hogged CPU for >13333us 8 times, consider switching to WQ_UNBOUND
[ 1665.284542] workqueue: nfsd_file_gc_worker [nfsd] hogged CPU for >13333us 16 times, consider switching to WQ_UNBOUND
[ 1759.491342] workqueue: nfsd_file_gc_worker [nfsd] hogged CPU for >13333us 32 times, consider switching to WQ_UNBOUND
[ 3013.012308] workqueue: nfsd_file_gc_worker [nfsd] hogged CPU for >13333us 64 times, consider switching to WQ_UNBOUND
[ 3154.172827] workqueue: nfsd_file_gc_worker [nfsd] hogged CPU for >13333us 128 times, consider switching to WQ_UNBOUND
[ 3422.461924] workqueue: nfsd_file_gc_worker [nfsd] hogged CPU for >13333us 256 times, consider switching to WQ_UNBOUND
[ 3963.152054] workqueue: nfsd_file_gc_worker [nfsd] hogged CPU for >13333us 512 times, consider switching to WQ_UNBOUND
Consider use system_unbound_wq instead of system_wq for
nfsd_file_gc_worker().
Signed-off-by: Youzhong Yang <youzhong@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
We already count the frees (via nfsd_file_releases). Count the
allocations as well. Also switch the direct call to nfsd_file_slab_free
in nfsd_file_do_acquire to nfsd_file_free, so that the allocs and
releases match up.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
If we wait_for_construction and find that the file is no longer hashed,
and we're going to retry the open, the old nfsd_file reference is
currently leaked. Put the reference before retrying.
Fixes: c6593366c0 ("nfsd: don't kill nfsd_files because of lease break error")
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Youzhong Yang <youzhong@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Given that we do the search and insertion while holding the i_lock, I
don't think it's possible for us to get EEXIST here. Remove this case.
Fixes: c6593366c0 ("nfsd: don't kill nfsd_files because of lease break error")
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Youzhong Yang <youzhong@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
nfsd_file_put() in one thread can race with another thread doing
garbage collection (running nfsd_file_gc() -> list_lru_walk() ->
nfsd_file_lru_cb()):
* In nfsd_file_put(), nf->nf_ref is 1, so it tries to do nfsd_file_lru_add().
* nfsd_file_lru_add() returns true (with NFSD_FILE_REFERENCED bit set)
* garbage collector kicks in, nfsd_file_lru_cb() clears REFERENCED bit and
returns LRU_ROTATE.
* garbage collector kicks in again, nfsd_file_lru_cb() now decrements nf->nf_ref
to 0, runs nfsd_file_unhash(), removes it from the LRU and adds to the dispose
list [list_lru_isolate_move(lru, &nf->nf_lru, head)]
* nfsd_file_put() detects NFSD_FILE_HASHED bit is cleared, so it tries to remove
the 'nf' from the LRU [if (!nfsd_file_lru_remove(nf))]. The 'nf' has been added
to the 'dispose' list by nfsd_file_lru_cb(), so nfsd_file_lru_remove(nf) simply
treats it as part of the LRU and removes it, which leads to its removal from
the 'dispose' list.
* At this moment, 'nf' is unhashed with its nf_ref being 0, and not on the LRU.
nfsd_file_put() continues its execution [if (refcount_dec_and_test(&nf->nf_ref))],
as nf->nf_ref is already 0, nf->nf_ref is set to REFCOUNT_SATURATED, and the 'nf'
gets no chance of being freed.
nfsd_file_put() can also race with nfsd_file_cond_queue():
* In nfsd_file_put(), nf->nf_ref is 1, so it tries to do nfsd_file_lru_add().
* nfsd_file_lru_add() sets REFERENCED bit and returns true.
* Some userland application runs 'exportfs -f' or something like that, which triggers
__nfsd_file_cache_purge() -> nfsd_file_cond_queue().
* In nfsd_file_cond_queue(), it runs [if (!nfsd_file_unhash(nf))], unhash is done
successfully.
* nfsd_file_cond_queue() runs [if (!nfsd_file_get(nf))], now nf->nf_ref goes to 2.
* nfsd_file_cond_queue() runs [if (nfsd_file_lru_remove(nf))], it succeeds.
* nfsd_file_cond_queue() runs [if (refcount_sub_and_test(decrement, &nf->nf_ref))]
(with "decrement" being 2), so the nf->nf_ref goes to 0, the 'nf' is added to the
dispose list [list_add(&nf->nf_lru, dispose)]
* nfsd_file_put() detects NFSD_FILE_HASHED bit is cleared, so it tries to remove
the 'nf' from the LRU [if (!nfsd_file_lru_remove(nf))], although the 'nf' is not
in the LRU, but it is linked in the 'dispose' list, nfsd_file_lru_remove() simply
treats it as part of the LRU and removes it. This leads to its removal from
the 'dispose' list!
* Now nf->ref is 0, unhashed. nfsd_file_put() continues its execution and set
nf->nf_ref to REFCOUNT_SATURATED.
As shown in the above analysis, using nf_lru for both the LRU list and dispose list
can cause the leaks. This patch adds a new list_head nf_gc in struct nfsd_file, and uses
it for the dispose list. This does not fix the nfsd_file leaking issue completely.
Signed-off-by: Youzhong Yang <youzhong@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
In the LTC2991, V5 and V6 channels use the low nibble of the
"V5, V6, V7, and V8 Control Register" for configuration, but currently,
the high nibble is defined.
This patch changes the defines to use the low nibble.
Fixes: 2b9ea4262a ("hwmon: Add driver for ltc2991")
Signed-off-by: Pawel Dembicki <paweldembicki@gmail.com>
Message-ID: <20240830111349.30531-1-paweldembicki@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Commit 5ce2176b81 ("genksyms: adjust the output format to modpost")
stopped generating *.symversions files.
Remove the left-over from the .gitignore file and the 'clean' rule.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
With commit cda5f94e88 ("modpost: avoid using the alias attribute"),
only two log levels remain: LOG_WARN and LOG_ERROR. Simplify this by
making it a boolean variable.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
objtree is defined and exported by the top-level Makefile. I prefer
not to override it.
There is no need to pass the absolute path of objtree. PKGBUILD can
detect it by itself.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Christian Heusel <christian@heusel.eu>
All build and package functions share the following commands:
export MAKEFLAGS="${KBUILD_MAKEFLAGS}"
cd "${objtree}"
Factor out the common code.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Christian Heusel <christian@heusel.eu>
Introduce the PACMAN_EXTRAPACKAGES variable in PKGBUILD to allow users
to specify which additional packages are built by the pacman-pkg target.
Previously, the api-headers package was always included, and the headers
package was included only if CONFIG_MODULES=y. With this change, both
headers and api-headers packages are included by default. Users can now
control this behavior by setting PACMAN_EXTRAPACKAGES to a
space-separated list of desired extra packages or leaving it empty to
exclude all.
For example, to build only the base package without extras:
make pacman-pkg PACMAN_EXTRAPACKAGES=""
Signed-off-by: Jose Fernandez <jose.fernandez@linux.dev>
Reviewed-by: Peter Jung <ptr1337@cachyos.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Christian Heusel <christian@heusel.eu>
Tested-by: Christian Heusel <christian@heusel.eu>
Acked-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
This commit improves the section mismatch warning format when there is
no suitable symbol name to print.
The section mismatch warning prints the reference source in the form
of <symbol_name>+<offset> and the reference destination in the form
of <symbol_name>.
However, there are some corner cases where <symbol_name> becomes
"(unknown)", as reported in commit 23dfd914d2 ("modpost: fix null
pointer dereference").
In such cases, it is better to print the symbol address.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
When malloc() fails, there is not much userspace programs can do.
xmalloc() is useful to bail out on a memory allocation failure.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
When malloc() or realloc() fails, there is not much userspace programs
can do. xmalloc() and xrealloc() are useful to bail out on a memory
allocation failure.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
P_SYMBOL is a pseudo property that was previously used for data linking
purposes.
It is no longer used except for debug prints. Remove it.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
I believe its last usage was in the following code:
if (prop == NULL)
prop = stack->sym->prop;
This code was previously used to print the file name and line number of
associated symbols in sym_check_print_recursive(), which was removed by
commit 9d0d266046 ("kconfig: recursive checks drop file/lineno").
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Since commit ca4c74ba30 ("kconfig: remove P_CHOICE property"),
menu_finalize() no longer calls menu_add_symbol(). No function
references cur_filename or cur_lineno after yyparse().
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
This reverts the following commits:
- 236dec0510 ("kconfig: tinyconfig: provide whole choice blocks to
avoid warnings")
- b0f269728c ("x86/config: Fix warning for 'make ARCH=x86_64
tinyconfig'")
Since commit f79dc03fe6 ("kconfig: refactor choice value calculation"),
it is no longer necessary to disable the remaining options in choice
blocks.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Parallel execution is supported by GNU Make:
$ make -j<N> modules_install
It is questionable to enable multithreading within each zstd process
by default.
If you still want to do it, you can use the environment variable:
$ ZSTD_NBTHREADS=<N> make modules_install
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Commit 3f1b0e1f28 (".gitignore update") added *.orig and *.rej
patterns to .gitignore in v2.6.23. The commit message didn't give a
rationale. Later on, commit 1f5d3a6b65 ("Remove *.rej pattern from
.gitignore") removed the *.rej pattern in v2.6.26, on the rationale that
*.rej files indicated something went really wrong and should not be
ignored.
The *.rej files are now shown by `git status`, which helps located
conflicts when applying patches and lowers the probability that they
will go unnoticed. It is however still easy to overlook the *.orig files
which slowly polute the source tree. That's not as big of a deal as not
noticing a conflict, but it's still not nice.
Drop the *.orig pattern from .gitignore to avoid this and help keep the
source tree clean.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
[masahiroy@kernel.org:
I do not have a strong opinion about this. Perhaps some people may have
a different opinion.
If you are someone who wants to ignore *.orig, it is likely you would
want to do so across all projects. Then, $XDG_CONFIG_HOME/git/ignore
would be more suitable for your needs. gitignore(5) suggests, "Patterns
which a user wants Git to ignore in all situations generally go into a
file specified by core.excludesFile in the user's ~/.gitconfig".
Please note that you cannot do the opposite; if *.orig is ignored by
the project's .gitignore, you cannot override the decision because
$XDG_CONFIG_HOME/git/ignore has a lower priority.
If *.orig is sitting on the fence, I'd leave it to the users. ]
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
A long standing issue in the upstream kernel packaging is that the
linux-headers package is not cross-compiled.
For example, you can cross-build Debian packages for arm64 by running
the following command:
$ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- bindeb-pkg
However, the generated linux-headers-*_arm64.deb is useless because the
host programs in it were built for your build machine architecture
(likely x86), not arm64.
The Debian kernel maintains its own Makefiles to cross-compile host
tools without relying on Kbuild. [1]
Instead of adding such full custom Makefiles, this commit adds a small
piece of code to cross-compile host programs located under the scripts/
directory.
A straightforward solution is to pass HOSTCC=${CROSS_COMPILE}gcc, but it
would also cross-compile scripts/basic/fixdep, which needs to be native
to process the if_changed_dep macro. (This approach may work under some
circumstances; you can execute foreign architecture programs with the
help of binfmt_misc because Debian systems enable CONFIG_BINFMT_MISC,
but it would require installing QEMU and libc for that architecture.)
A trick is to use the external module build (KBUILD_EXTMOD=), which
does not rebuild scripts/basic/fixdep. ${CC} needs to be able to link
userspace programs (CONFIG_CC_CAN_LINK=y).
There are known limitations:
- GCC plugins
It would possible to rebuild GCC plugins for the target architecture
by passing HOSTCXX=${CROSS_COMPILE}g++ with necessary packages
installed, but gcc on the installed system emits
"cc1: error: incompatible gcc/plugin versions".
- objtool and resolve_btfids
These are built by the tools build system. They are not covered by
the current solution. The resulting linux-headers package is broken
if CONFIG_OBJTOOL or CONFIG_DEBUG_INFO_BTF is enabled.
I only tested this with Debian, but it should work for other package
systems as well.
[1]: https://salsa.debian.org/kernel-team/linux/-/blob/debian/6.9.9-1/debian/rules.real#L586
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Endianness is currently detected on compile-time, but we can defer this
until run-time. This change avoids re-executing scripts/mod/mk_elfconfig
even if modpost in the linux-headers package needs to be rebuilt for a
foreign architecture.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
HOST_ELFCLASS is output to elfconfig.h, but it is not used in modpost.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
