Commit Graph

640 Commits

Author SHA1 Message Date
Masahiro Yamada
6691e6f5fc modpost: remove get_prettyname()
This is the last user of get_pretty_name() - it is just used to
distinguish whether the symbol is a function or not. It is not
valuable information.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-05-22 10:34:38 +09:00
Masahiro Yamada
6c90d36be3 modpost: remove fromsym info in __ex_table section mismatch warning
report_extable_warnings() prints "from" in a pretty form, but we know
it is always located in the __ex_table section, i.e. a collection of
struct exception_table_entry.

It is very likely to fail to get the symbol name and ends up with
meaningless message:

  ... in reference from the (unknown reference) (unknown) to ...

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-05-22 10:34:38 +09:00
Masahiro Yamada
d0acc76a49 modpost: remove broken calculation of exception_table_entry size
find_extable_entry_size() is completely broken. It has awesome comments
about how to calculate sizeof(struct exception_table_entry).

It was based on these assumptions:

  - struct exception_table_entry has two fields
  - both of the fields have the same size

Then, we came up with this equation:

  (offset of the second field) * 2 == (size of struct)

It was true for all architectures when commit 52dc0595d5 ("modpost:
handle relocations mismatch in __ex_table.") was applied.

Our mathematics broke when commit 548acf1923 ("x86/mm: Expand the
exception table logic to allow new handling options") introduced the
third field.

Now, the definition of exception_table_entry is highly arch-dependent.

For x86, sizeof(struct exception_table_entry) is apparently 12, but
find_extable_entry_size() sets extable_entry_size to 8.

I could fix it, but I do not see much value in this code.

extable_entry_size is used just for selecting a slightly different
error message.

If the first field ("insn") references to a non-executable section,

    The relocation at %s+0x%lx references
    section "%s" which is not executable, IOW
    it is not possible for the kernel to fault
    at that address.  Something is seriously wrong
    and should be fixed.

If the second field ("fixup") references to a non-executable section,

    The relocation at %s+0x%lx references
    section "%s" which is not executable, IOW
    the kernel will fault if it ever tries to
    jump to it.  Something is seriously wrong
    and should be fixed.

Merge the two error messages rather than adding even more complexity.

Change fatal() to error() to make it continue running and catch more
possible errors.

Fixes: 548acf1923 ("x86/mm: Expand the exception table logic to allow new handling options")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-05-22 10:34:38 +09:00
Masahiro Yamada
64f140417d modpost: error out if addend_*_rel() is not implemented for REL arch
The section mismatch check relies on the relocation entries.

For REL, the addend value is implicit, so we need some code to compute
it. Currently, EM_386, EM_ARM, and EM_MIPS are supported. This commit
makes sure we covered all the cases.

I believe the other architectures use RELA, where the explicit r_addend
field exists.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-05-22 10:34:38 +09:00
Linus Torvalds
b6a7828502 modules-6.4-rc1
The summary of the changes for this pull requests is:
 
  * Song Liu's new struct module_memory replacement
  * Nick Alcock's MODULE_LICENSE() removal for non-modules
  * My cleanups and enhancements to reduce the areas where we vmalloc
    module memory for duplicates, and the respective debug code which
    proves the remaining vmalloc pressure comes from userspace.
 
 Most of the changes have been in linux-next for quite some time except
 the minor fixes I made to check if a module was already loaded
 prior to allocating the final module memory with vmalloc and the
 respective debug code it introduces to help clarify the issue. Although
 the functional change is small it is rather safe as it can only *help*
 reduce vmalloc space for duplicates and is confirmed to fix a bootup
 issue with over 400 CPUs with KASAN enabled. I don't expect stable
 kernels to pick up that fix as the cleanups would have also had to have
 been picked up. Folks on larger CPU systems with modules will want to
 just upgrade if vmalloc space has been an issue on bootup.
 
 Given the size of this request, here's some more elaborate details
 on this pull request.
 
 The functional change change in this pull request is the very first
 patch from Song Liu which replaces the struct module_layout with a new
 struct module memory. The old data structure tried to put together all
 types of supported module memory types in one data structure, the new
 one abstracts the differences in memory types in a module to allow each
 one to provide their own set of details. This paves the way in the
 future so we can deal with them in a cleaner way. If you look at changes
 they also provide a nice cleanup of how we handle these different memory
 areas in a module. This change has been in linux-next since before the
 merge window opened for v6.3 so to provide more than a full kernel cycle
 of testing. It's a good thing as quite a bit of fixes have been found
 for it.
 
 Jason Baron then made dynamic debug a first class citizen module user by
 using module notifier callbacks to allocate / remove module specific
 dynamic debug information.
 
 Nick Alcock has done quite a bit of work cross-tree to remove module
 license tags from things which cannot possibly be module at my request
 so to:
 
   a) help him with his longer term tooling goals which require a
      deterministic evaluation if a piece a symbol code could ever be
      part of a module or not. But quite recently it is has been made
      clear that tooling is not the only one that would benefit.
      Disambiguating symbols also helps efforts such as live patching,
      kprobes and BPF, but for other reasons and R&D on this area
      is active with no clear solution in sight.
 
   b) help us inch closer to the now generally accepted long term goal
      of automating all the MODULE_LICENSE() tags from SPDX license tags
 
 In so far as a) is concerned, although module license tags are a no-op
 for non-modules, tools which would want create a mapping of possible
 modules can only rely on the module license tag after the commit
 8b41fc4454 ("kbuild: create modules.builtin without Makefile.modbuiltin
 or tristate.conf").  Nick has been working on this *for years* and
 AFAICT I was the only one to suggest two alternatives to this approach
 for tooling. The complexity in one of my suggested approaches lies in
 that we'd need a possible-obj-m and a could-be-module which would check
 if the object being built is part of any kconfig build which could ever
 lead to it being part of a module, and if so define a new define
 -DPOSSIBLE_MODULE [0]. A more obvious yet theoretical approach I've
 suggested would be to have a tristate in kconfig imply the same new
 -DPOSSIBLE_MODULE as well but that means getting kconfig symbol names
 mapping to modules always, and I don't think that's the case today. I am
 not aware of Nick or anyone exploring either of these options. Quite
 recently Josh Poimboeuf has pointed out that live patching, kprobes and
 BPF would benefit from resolving some part of the disambiguation as
 well but for other reasons. The function granularity KASLR (fgkaslr)
 patches were mentioned but Joe Lawrence has clarified this effort has
 been dropped with no clear solution in sight [1].
 
 In the meantime removing module license tags from code which could never
 be modules is welcomed for both objectives mentioned above. Some
 developers have also welcomed these changes as it has helped clarify
 when a module was never possible and they forgot to clean this up,
 and so you'll see quite a bit of Nick's patches in other pull
 requests for this merge window. I just picked up the stragglers after
 rc3. LWN has good coverage on the motivation behind this work [2] and
 the typical cross-tree issues he ran into along the way. The only
 concrete blocker issue he ran into was that we should not remove the
 MODULE_LICENSE() tags from files which have no SPDX tags yet, even if
 they can never be modules. Nick ended up giving up on his efforts due
 to having to do this vetting and backlash he ran into from folks who
 really did *not understand* the core of the issue nor were providing
 any alternative / guidance. I've gone through his changes and dropped
 the patches which dropped the module license tags where an SPDX
 license tag was missing, it only consisted of 11 drivers.  To see
 if a pull request deals with a file which lacks SPDX tags you
 can just use:
 
   ./scripts/spdxcheck.py -f \
 	$(git diff --name-only commid-id | xargs echo)
 
 You'll see a core module file in this pull request for the above,
 but that's not related to his changes. WE just need to add the SPDX
 license tag for the kernel/module/kmod.c file in the future but
 it demonstrates the effectiveness of the script.
 
 Most of Nick's changes were spread out through different trees,
 and I just picked up the slack after rc3 for the last kernel was out.
 Those changes have been in linux-next for over two weeks.
 
 The cleanups, debug code I added and final fix I added for modules
 were motivated by David Hildenbrand's report of boot failing on
 a systems with over 400 CPUs when KASAN was enabled due to running
 out of virtual memory space. Although the functional change only
 consists of 3 lines in the patch "module: avoid allocation if module is
 already present and ready", proving that this was the best we can
 do on the modules side took quite a bit of effort and new debug code.
 
 The initial cleanups I did on the modules side of things has been
 in linux-next since around rc3 of the last kernel, the actual final
 fix for and debug code however have only been in linux-next for about a
 week or so but I think it is worth getting that code in for this merge
 window as it does help fix / prove / evaluate the issues reported
 with larger number of CPUs. Userspace is not yet fixed as it is taking
 a bit of time for folks to understand the crux of the issue and find a
 proper resolution. Worst come to worst, I have a kludge-of-concept [3]
 of how to make kernel_read*() calls for modules unique / converge them,
 but I'm currently inclined to just see if userspace can fix this
 instead.
 
 [0] https://lore.kernel.org/all/Y/kXDqW+7d71C4wz@bombadil.infradead.org/
 [1] https://lkml.kernel.org/r/025f2151-ce7c-5630-9b90-98742c97ac65@redhat.com
 [2] https://lwn.net/Articles/927569/
 [3] https://lkml.kernel.org/r/20230414052840.1994456-3-mcgrof@kernel.org
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Merge tag 'modules-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux

Pull module updates from Luis Chamberlain:
 "The summary of the changes for this pull requests is:

   - Song Liu's new struct module_memory replacement

   - Nick Alcock's MODULE_LICENSE() removal for non-modules

   - My cleanups and enhancements to reduce the areas where we vmalloc
     module memory for duplicates, and the respective debug code which
     proves the remaining vmalloc pressure comes from userspace.

  Most of the changes have been in linux-next for quite some time except
  the minor fixes I made to check if a module was already loaded prior
  to allocating the final module memory with vmalloc and the respective
  debug code it introduces to help clarify the issue. Although the
  functional change is small it is rather safe as it can only *help*
  reduce vmalloc space for duplicates and is confirmed to fix a bootup
  issue with over 400 CPUs with KASAN enabled. I don't expect stable
  kernels to pick up that fix as the cleanups would have also had to
  have been picked up. Folks on larger CPU systems with modules will
  want to just upgrade if vmalloc space has been an issue on bootup.

  Given the size of this request, here's some more elaborate details:

  The functional change change in this pull request is the very first
  patch from Song Liu which replaces the 'struct module_layout' with a
  new 'struct module_memory'. The old data structure tried to put
  together all types of supported module memory types in one data
  structure, the new one abstracts the differences in memory types in a
  module to allow each one to provide their own set of details. This
  paves the way in the future so we can deal with them in a cleaner way.
  If you look at changes they also provide a nice cleanup of how we
  handle these different memory areas in a module. This change has been
  in linux-next since before the merge window opened for v6.3 so to
  provide more than a full kernel cycle of testing. It's a good thing as
  quite a bit of fixes have been found for it.

  Jason Baron then made dynamic debug a first class citizen module user
  by using module notifier callbacks to allocate / remove module
  specific dynamic debug information.

  Nick Alcock has done quite a bit of work cross-tree to remove module
  license tags from things which cannot possibly be module at my request
  so to:

   a) help him with his longer term tooling goals which require a
      deterministic evaluation if a piece a symbol code could ever be
      part of a module or not. But quite recently it is has been made
      clear that tooling is not the only one that would benefit.
      Disambiguating symbols also helps efforts such as live patching,
      kprobes and BPF, but for other reasons and R&D on this area is
      active with no clear solution in sight.

   b) help us inch closer to the now generally accepted long term goal
      of automating all the MODULE_LICENSE() tags from SPDX license tags

  In so far as a) is concerned, although module license tags are a no-op
  for non-modules, tools which would want create a mapping of possible
  modules can only rely on the module license tag after the commit
  8b41fc4454 ("kbuild: create modules.builtin without
  Makefile.modbuiltin or tristate.conf").

  Nick has been working on this *for years* and AFAICT I was the only
  one to suggest two alternatives to this approach for tooling. The
  complexity in one of my suggested approaches lies in that we'd need a
  possible-obj-m and a could-be-module which would check if the object
  being built is part of any kconfig build which could ever lead to it
  being part of a module, and if so define a new define
  -DPOSSIBLE_MODULE [0].

  A more obvious yet theoretical approach I've suggested would be to
  have a tristate in kconfig imply the same new -DPOSSIBLE_MODULE as
  well but that means getting kconfig symbol names mapping to modules
  always, and I don't think that's the case today. I am not aware of
  Nick or anyone exploring either of these options. Quite recently Josh
  Poimboeuf has pointed out that live patching, kprobes and BPF would
  benefit from resolving some part of the disambiguation as well but for
  other reasons. The function granularity KASLR (fgkaslr) patches were
  mentioned but Joe Lawrence has clarified this effort has been dropped
  with no clear solution in sight [1].

  In the meantime removing module license tags from code which could
  never be modules is welcomed for both objectives mentioned above. Some
  developers have also welcomed these changes as it has helped clarify
  when a module was never possible and they forgot to clean this up, and
  so you'll see quite a bit of Nick's patches in other pull requests for
  this merge window. I just picked up the stragglers after rc3. LWN has
  good coverage on the motivation behind this work [2] and the typical
  cross-tree issues he ran into along the way. The only concrete blocker
  issue he ran into was that we should not remove the MODULE_LICENSE()
  tags from files which have no SPDX tags yet, even if they can never be
  modules. Nick ended up giving up on his efforts due to having to do
  this vetting and backlash he ran into from folks who really did *not
  understand* the core of the issue nor were providing any alternative /
  guidance. I've gone through his changes and dropped the patches which
  dropped the module license tags where an SPDX license tag was missing,
  it only consisted of 11 drivers. To see if a pull request deals with a
  file which lacks SPDX tags you can just use:

    ./scripts/spdxcheck.py -f \
	$(git diff --name-only commid-id | xargs echo)

  You'll see a core module file in this pull request for the above, but
  that's not related to his changes. WE just need to add the SPDX
  license tag for the kernel/module/kmod.c file in the future but it
  demonstrates the effectiveness of the script.

  Most of Nick's changes were spread out through different trees, and I
  just picked up the slack after rc3 for the last kernel was out. Those
  changes have been in linux-next for over two weeks.

  The cleanups, debug code I added and final fix I added for modules
  were motivated by David Hildenbrand's report of boot failing on a
  systems with over 400 CPUs when KASAN was enabled due to running out
  of virtual memory space. Although the functional change only consists
  of 3 lines in the patch "module: avoid allocation if module is already
  present and ready", proving that this was the best we can do on the
  modules side took quite a bit of effort and new debug code.

  The initial cleanups I did on the modules side of things has been in
  linux-next since around rc3 of the last kernel, the actual final fix
  for and debug code however have only been in linux-next for about a
  week or so but I think it is worth getting that code in for this merge
  window as it does help fix / prove / evaluate the issues reported with
  larger number of CPUs. Userspace is not yet fixed as it is taking a
  bit of time for folks to understand the crux of the issue and find a
  proper resolution. Worst come to worst, I have a kludge-of-concept [3]
  of how to make kernel_read*() calls for modules unique / converge
  them, but I'm currently inclined to just see if userspace can fix this
  instead"

Link: https://lore.kernel.org/all/Y/kXDqW+7d71C4wz@bombadil.infradead.org/ [0]
Link: https://lkml.kernel.org/r/025f2151-ce7c-5630-9b90-98742c97ac65@redhat.com [1]
Link: https://lwn.net/Articles/927569/ [2]
Link: https://lkml.kernel.org/r/20230414052840.1994456-3-mcgrof@kernel.org [3]

* tag 'modules-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (121 commits)
  module: add debugging auto-load duplicate module support
  module: stats: fix invalid_mod_bytes typo
  module: remove use of uninitialized variable len
  module: fix building stats for 32-bit targets
  module: stats: include uapi/linux/module.h
  module: avoid allocation if module is already present and ready
  module: add debug stats to help identify memory pressure
  module: extract patient module check into helper
  modules/kmod: replace implementation with a semaphore
  Change DEFINE_SEMAPHORE() to take a number argument
  module: fix kmemleak annotations for non init ELF sections
  module: Ignore L0 and rename is_arm_mapping_symbol()
  module: Move is_arm_mapping_symbol() to module_symbol.h
  module: Sync code of is_arm_mapping_symbol()
  scripts/gdb: use mem instead of core_layout to get the module address
  interconnect: remove module-related code
  interconnect: remove MODULE_LICENSE in non-modules
  zswap: remove MODULE_LICENSE in non-modules
  zpool: remove MODULE_LICENSE in non-modules
  x86/mm/dump_pagetables: remove MODULE_LICENSE in non-modules
  ...
2023-04-27 16:36:55 -07:00
Tiezhu Yang
0a3bf86092 module: Ignore L0 and rename is_arm_mapping_symbol()
The L0 symbol is generated when build module on LoongArch, ignore it in
modpost and when looking at module symbols, otherwise we can not see the
expected call trace.

Now is_arm_mapping_symbol() is not only for ARM, in order to reflect the
reality, rename is_arm_mapping_symbol() to is_mapping_symbol().

This is related with commit c17a253870 ("mksysmap: Fix the mismatch of
'L0' symbols in System.map").

(1) Simple test case

  [loongson@linux hello]$ cat hello.c
  #include <linux/init.h>
  #include <linux/module.h>
  #include <linux/printk.h>

  static void test_func(void)
  {
  	  pr_info("This is a test\n");
	  dump_stack();
  }

  static int __init hello_init(void)
  {
	  pr_warn("Hello, world\n");
	  test_func();

	  return 0;
  }

  static void __exit hello_exit(void)
  {
	  pr_warn("Goodbye\n");
  }

  module_init(hello_init);
  module_exit(hello_exit);
  MODULE_LICENSE("GPL");
  [loongson@linux hello]$ cat Makefile
  obj-m:=hello.o

  ccflags-y += -g -Og

  all:
	  make -C /lib/modules/$(shell uname -r)/build/ M=$(PWD) modules
  clean:
	  make -C /lib/modules/$(shell uname -r)/build/ M=$(PWD) clean

(2) Test environment

system: LoongArch CLFS 5.5
https://github.com/sunhaiyong1978/CLFS-for-LoongArch/releases/tag/5.0
It needs to update grub to avoid booting error "invalid magic number".

kernel: 6.3-rc1 with loongson3_defconfig + CONFIG_DYNAMIC_FTRACE=y

(3) Test result

Without this patch:

  [root@linux hello]# insmod hello.ko
  [root@linux hello]# dmesg
  ...
  Hello, world
  This is a test
  ...
  Call Trace:
  [<9000000000223728>] show_stack+0x68/0x18c
  [<90000000013374cc>] dump_stack_lvl+0x60/0x88
  [<ffff800002050028>] L0\x01+0x20/0x2c [hello]
  [<ffff800002058028>] L0\x01+0x20/0x30 [hello]
  [<900000000022097c>] do_one_initcall+0x88/0x288
  [<90000000002df890>] do_init_module+0x54/0x200
  [<90000000002e1e18>] __do_sys_finit_module+0xc4/0x114
  [<90000000013382e8>] do_syscall+0x7c/0x94
  [<9000000000221e3c>] handle_syscall+0xbc/0x158

With this patch:

  [root@linux hello]# insmod hello.ko
  [root@linux hello]# dmesg
  ...
  Hello, world
  This is a test
  ...
  Call Trace:
  [<9000000000223728>] show_stack+0x68/0x18c
  [<90000000013374cc>] dump_stack_lvl+0x60/0x88
  [<ffff800002050028>] test_func+0x28/0x34 [hello]
  [<ffff800002058028>] hello_init+0x28/0x38 [hello]
  [<900000000022097c>] do_one_initcall+0x88/0x288
  [<90000000002df890>] do_init_module+0x54/0x200
  [<90000000002e1e18>] __do_sys_finit_module+0xc4/0x114
  [<90000000013382e8>] do_syscall+0x7c/0x94
  [<9000000000221e3c>] handle_syscall+0xbc/0x158

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Tested-by: Youling Tang <tangyouling@loongson.cn> # for LoongArch
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-04-13 17:15:50 -07:00
Tiezhu Yang
987d2e0aaa module: Move is_arm_mapping_symbol() to module_symbol.h
In order to avoid duplicated code, move is_arm_mapping_symbol() to
include/linux/module_symbol.h, then remove is_arm_mapping_symbol()
in the other places.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-04-13 17:15:49 -07:00
Tiezhu Yang
87e5b1e8f2 module: Sync code of is_arm_mapping_symbol()
After commit 2e3a10a155 ("ARM: avoid ARM binutils leaking ELF local
symbols") and commit d6b732666a ("modpost: fix undefined behavior of
is_arm_mapping_symbol()"), many differences of is_arm_mapping_symbol()
exist in kernel/module/kallsyms.c and scripts/mod/modpost.c, just sync
the code to keep consistent.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-04-13 17:15:49 -07:00
Greg Kroah-Hartman
5790d407da Merge 6.3-rc6 into char-misc-next
We need it here to apply other char/misc driver changes to.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-10 08:49:26 +02:00
Nipun Gupta
2959ab2470 cdx: add the cdx bus driver
Introduce AMD CDX bus, which provides a mechanism for scanning
and probing CDX devices. These devices are memory mapped on
system bus for Application Processors(APUs).

CDX devices can be changed dynamically in the Fabric and CDX
bus interacts with CDX controller to rescan the bus and
rediscover the devices.

Signed-off-by: Nipun Gupta <nipun.gupta@amd.com>
Reviewed-by: Pieter Jansen van Vuuren <pieter.jansen-van-vuuren@amd.com>
Tested-by: Nikhil Agarwal <nikhil.agarwal@amd.com>
Link: https://lore.kernel.org/r/20230313132636.31850-2-nipun.gupta@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-29 12:26:32 +02:00
Ben Hutchings
fb27e70f6e modpost: Fix processing of CRCs on 32-bit build machines
modpost now reads CRCs from .*.cmd files, parsing them using strtol().
This is inconsistent with its parsing of Module.symvers and with their
definition as *unsigned* 32-bit values.

strtol() clamps values to [LONG_MIN, LONG_MAX], and when building on a
32-bit system this changes all CRCs >= 0x80000000 to be 0x7fffffff.

Change extract_crcs_for_object() to use strtoul() instead.

Cc: stable@vger.kernel.org
Fixes: f292d875d0 ("modpost: extract symbol versions from *.cmd files")
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-03-23 15:28:41 +09:00
Linus Torvalds
6feb57c2fd Kbuild updates for v6.2
- Support zstd-compressed debug info
 
  - Allow W=1 builds to detect objects shared among multiple modules
 
  - Add srcrpm-pkg target to generate a source RPM package
 
  - Make the -s option detection work for future GNU Make versions
 
  - Add -Werror to KBUILD_CPPFLAGS when CONFIG_WERROR=y
 
  - Allow W=1 builds to detect -Wundef warnings in any preprocessed files
 
  - Raise the minimum supported version of binutils to 2.25
 
  - Use $(intcmp ...) to compare integers if GNU Make >= 4.4 is used
 
  - Use $(file ...) to read a file if GNU Make >= 4.2 is used
 
  - Print error if GNU Make older than 3.82 is used
 
  - Allow modpost to detect section mismatches with Clang LTO
 
  - Include vmlinuz.efi into kernel tarballs for arm64 CONFIG_EFI_ZBOOT=y
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Merge tag 'kbuild-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - Support zstd-compressed debug info

 - Allow W=1 builds to detect objects shared among multiple modules

 - Add srcrpm-pkg target to generate a source RPM package

 - Make the -s option detection work for future GNU Make versions

 - Add -Werror to KBUILD_CPPFLAGS when CONFIG_WERROR=y

 - Allow W=1 builds to detect -Wundef warnings in any preprocessed files

 - Raise the minimum supported version of binutils to 2.25

 - Use $(intcmp ...) to compare integers if GNU Make >= 4.4 is used

 - Use $(file ...) to read a file if GNU Make >= 4.2 is used

 - Print error if GNU Make older than 3.82 is used

 - Allow modpost to detect section mismatches with Clang LTO

 - Include vmlinuz.efi into kernel tarballs for arm64 CONFIG_EFI_ZBOOT=y

* tag 'kbuild-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (29 commits)
  buildtar: fix tarballs with EFI_ZBOOT enabled
  modpost: Include '.text.*' in TEXT_SECTIONS
  padata: Mark padata_work_init() as __ref
  kbuild: ensure Make >= 3.82 is used
  kbuild: refactor the prerequisites of the modpost rule
  kbuild: change module.order to list *.o instead of *.ko
  kbuild: use .NOTINTERMEDIATE for future GNU Make versions
  kconfig: refactor Makefile to reduce process forks
  kbuild: add read-file macro
  kbuild: do not sort after reading modules.order
  kbuild: add test-{ge,gt,le,lt} macros
  Documentation: raise minimum supported version of binutils to 2.25
  kbuild: add -Wundef to KBUILD_CPPFLAGS for W=1 builds
  kbuild: move -Werror from KBUILD_CFLAGS to KBUILD_CPPFLAGS
  kbuild: Port silent mode detection to future gnu make.
  init/version.c: remove #include <generated/utsrelease.h>
  firmware_loader: remove #include <generated/utsrelease.h>
  modpost: Mark uuid_le type to be suitable only for MEI
  kbuild: add ability to make source rpm buildable using koji
  kbuild: warn objects shared among multiple modules
  ...
2022-12-19 12:33:32 -06:00
Nathan Chancellor
19331e84c3 modpost: Include '.text.*' in TEXT_SECTIONS
Commit 6c730bfc89 ("modpost: handle -ffunction-sections") added
".text.*" to the OTHER_TEXT_SECTIONS macro to fix certain section
mismatch warnings. Unfortunately, this makes it impossible for modpost
to warn about section mismatches with LTO, which implies
'-ffunction-sections', as all functions are put in their own
'.text.<func_name>' sections, which may still reference functions in
sections they are not supposed to, such as __init.

Fix this by moving ".text.*" into TEXT_SECTIONS, so that configurations
with '-ffunction-sections' will see warnings about mismatched sections.

Link: https://lore.kernel.org/Y39kI3MOtVI5BAnV@google.com/
Reported-by: Vincent Donnefort <vdonnefort@google.com>
Reviewed-and-tested-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-12-14 15:49:34 +09:00
Masahiro Yamada
f65a486821 kbuild: change module.order to list *.o instead of *.ko
scripts/Makefile.build replaces the suffix .o with .ko, then
scripts/Makefile.modpost calls the sed command to change .ko back
to the original .o suffix.

Instead of converting the suffixes back-and-forth, store the .o paths
in modules.order, and replace it with .ko in 'make modules_install'.

This avoids the unneeded sed command.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
2022-12-14 15:42:40 +09:00
Youling Tang
3d36f4298b LoongArch: Switch to relative exception tables
Similar to other architectures such as arm64, x86, riscv and so on, use
offsets relative to the exception table entry values rather than their
absolute addresses for both the exception location and the fixup.

However, LoongArch label difference because it will actually produce two
relocations, a pair of R_LARCH_ADD32 and R_LARCH_SUB32. Take simple code
below for example:

$ cat test_ex_table.S
.section .text
1:
        nop
.section __ex_table,"a"
        .balign 4
        .long (1b - .)
.previous

$ loongarch64-unknown-linux-gnu-gcc -c test_ex_table.S
$ loongarch64-unknown-linux-gnu-readelf -Wr test_ex_table.o

Relocation section '.rela__ex_table' at offset 0x100 contains 2 entries:
    Offset            Info             Type         Symbol's Value   Symbol's Name + Addend
0000000000000000 0000000600000032 R_LARCH_ADD32    0000000000000000  .L1^B1 + 0
0000000000000000 0000000500000037 R_LARCH_SUB32    0000000000000000  L0^A + 0

The modpost will complain the R_LARCH_SUB32 relocation, so we need to
patch modpost.c to skip this relocation for .rela__ex_table section.

Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-12-14 08:36:11 +08:00
Andy Shevchenko
248043299b modpost: Mark uuid_le type to be suitable only for MEI
The uuid_le type is used only in MEI ABI, do not advertise it for others.
While at it, comment out that UUID types are not to be used in a new code.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2022-11-27 08:08:16 +09:00
KaiLong Wang
30daacc571 modpost: fix array_size.cocci warning
Fix following coccicheck warning:

scripts/mod/sumversion.c:219:48-49: WARNING: Use ARRAY_SIZE
scripts/mod/sumversion.c:156:48-49: WARNING: Use ARRAY_SIZE

Signed-off-by: KaiLong Wang <wangkailong@jari.cn>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-11-21 10:18:39 +09:00
Geert Uytterhoeven
0d2573a2b7 modpost: Join broken long printed messages
Breaking long printed messages in multiple lines makes it very hard to
look up where they originated from.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-11-21 10:18:39 +09:00
Masahiro Yamada
5b8a9a8fd1 modpost: fix module versioning when a symbol lacks valid CRC
Since commit 7b4537199a ("kbuild: link symbol CRCs at final link,
removing CONFIG_MODULE_REL_CRCS"), module versioning is broken on
some architectures. Loading a module fails with "disagrees about
version of symbol module_layout".

On such architectures (e.g. ARCH=sparc build with sparc64_defconfig),
modpost shows a warning, like follows:

  WARNING: modpost: EXPORT symbol "_mcount" [vmlinux] version generation failed, symbol will not be versioned.
  Is "_mcount" prototyped in <asm/asm-prototypes.h>?

Previously, it was a harmless warning (CRC check was just skipped),
but now wrong CRCs are used for comparison because invalid CRCs are
just skipped.

  $ sparc64-linux-gnu-nm -n vmlinux
    [snip]
  0000000000c2cea0 r __ksymtab__kstrtol
  0000000000c2ceb8 r __ksymtab__kstrtoul
  0000000000c2ced0 r __ksymtab__local_bh_enable
  0000000000c2cee8 r __ksymtab__mcount
  0000000000c2cf00 r __ksymtab__printk
  0000000000c2cf18 r __ksymtab__raw_read_lock
  0000000000c2cf30 r __ksymtab__raw_read_lock_bh
    [snip]
  0000000000c53b34 D __crc__kstrtol
  0000000000c53b38 D __crc__kstrtoul
  0000000000c53b3c D __crc__local_bh_enable
  0000000000c53b40 D __crc__printk
  0000000000c53b44 D __crc__raw_read_lock
  0000000000c53b48 D __crc__raw_read_lock_bh

Please notice __crc__mcount is missing here.

When the module subsystem looks up a CRC that comes after, it results
in reading out a wrong address. For example, when __crc__printk is
needed, the module subsystem reads 0xc53b44 instead of 0xc53b40.

All CRC entries must be output for correct index accessing. Invalid
CRCs will be unused, but are needed to keep the one-to-one mapping
between __ksymtab_* and __crc_*.

The best is to fix all modpost warnings, but several warnings are still
remaining on less popular architectures.

Fixes: 7b4537199a ("kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS")
Reported-by: matoro <matoro_mailinglist_kernel@matoro.tk>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: matoro <matoro_mailinglist_kernel@matoro.tk>
2022-08-21 02:47:36 +09:00
Linus Torvalds
0af5cb349a Kbuild updates for v5.20
- Remove the support for -O3 (CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3)
 
  - Fix error of rpm-pkg cross-builds
 
  - Support riscv for checkstack tool
 
  - Re-enable -Wformwat warnings for Clang
 
  - Clean up modpost, Makefiles, and misc scripts
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Merge tag 'kbuild-v5.20' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - Remove the support for -O3 (CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3)

 - Fix error of rpm-pkg cross-builds

 - Support riscv for checkstack tool

 - Re-enable -Wformwat warnings for Clang

 - Clean up modpost, Makefiles, and misc scripts

* tag 'kbuild-v5.20' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (30 commits)
  modpost: remove .symbol_white_list field entirely
  modpost: remove unneeded .symbol_white_list initializers
  modpost: add PATTERNS() helper macro
  modpost: shorten warning messages in report_sec_mismatch()
  Revert "Kbuild, lto, workaround: Don't warn for initcall_reference in modpost"
  modpost: use more reliable way to get fromsec in section_rel(a)()
  modpost: add array range check to sec_name()
  modpost: refactor get_secindex()
  kbuild: set EXIT trap before creating temporary directory
  modpost: remove unused Elf_Sword macro
  Makefile.extrawarn: re-enable -Wformat for clang
  kbuild: add dtbs_prepare target
  kconfig: Qt5: tell the user which packages are required
  modpost: use sym_get_data() to get module device_table data
  modpost: drop executable ELF support
  checkstack: add riscv support for scripts/checkstack.pl
  kconfig: shorten the temporary directory name for cc-option
  scripts: headers_install.sh: Update config leak ignore entries
  kbuild: error out if $(INSTALL_MOD_PATH) contains % or :
  kbuild: error out if $(KBUILD_EXTMOD) contains % or :
  ...
2022-08-10 10:40:41 -07:00
Masahiro Yamada
672fb6740c modpost: remove .symbol_white_list field entirely
It is not so useful to have symbol whitelists in arrays. With this
over-engineering, the code is difficult to follow.

Let's do it more directly, and collect the relevant code to one place.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-08-04 20:32:13 +09:00
Masahiro Yamada
1560cb0e18 modpost: remove unneeded .symbol_white_list initializers
The ->symbol_white_list field is referenced in secref_whitelist(),
only when 'fromsec' is data_sections.

        /* Check for pattern 2 */
        if (match(tosec, init_exit_sections) &&
            match(fromsec, data_sections) &&
            match(fromsym, mismatch->symbol_white_list))
                return 0;

If .fromsec is not data sections, the .symbol_white_list member is
not used by anyone.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-08-04 20:32:13 +09:00
Masahiro Yamada
7452dd26a5 modpost: add PATTERNS() helper macro
This will be useful to define a NULL-terminated array inside a function
call.

Currently, string arrays passed to match() are defined in separate
places:

    static const char *const init_sections[] = { ALL_INIT_SECTIONS, NULL };
    static const char *const text_sections[] = { ALL_TEXT_SECTIONS, NULL };
    static const char *const optim_symbols[] = { "*.constprop.*", NULL };

            ...

            /* Check for pattern 5 */
            if (match(fromsec, text_sections) &&
                match(tosec, init_sections) &&
                match(fromsym, optim_symbols))
                    return 0;

With the new helper macro, you can list the patterns directly in the
function call, like this:

            /* Check for pattern 5 */
            if (match(fromsec, PATTERNS(ALL_TEXT_SECTIONS)) &&
                match(tosec, PATTERNS(ALL_INIT_SECTIONS)) &&
                match(fromsym, PATTERNS("*.contprop.*")))
                    return 0;

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-08-04 20:32:13 +09:00
Masahiro Yamada
072dd2c892 modpost: shorten warning messages in report_sec_mismatch()
Each section mismatch results in long warning messages. Too much.

Make each warning fit in one line, and remove a lot of messy code.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-08-04 20:32:13 +09:00
Masahiro Yamada
a25efd6ef1 Revert "Kbuild, lto, workaround: Don't warn for initcall_reference in modpost"
This reverts commit 77ab21adae.

Even after 8 years later, GCC LTO has not been upstreamed. Also, it said
"This is a workaround". If this is needed in the future, it should be
added in a proper way.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Jiri Slaby <jirislaby@kernel.org>
2022-08-04 20:27:17 +09:00
Masahiro Yamada
5419aa2a8d modpost: use more reliable way to get fromsec in section_rel(a)()
The section name of Rel and Rela starts with ".rel" and ".rela"
respectively (but, I do not know whether this is specification or
convention).

For example, ".rela.text" holds relocation entries applied to the
".text" section.

So, the code chops the ".rel" or ".rela" prefix to get the name of
the section to which the relocation applies.

However, I do not like to skip 4 or 5 bytes blindly because it is
potential memory overrun.

The ELF specification provides a more reliable way to do this.

 - The sh_info field holds extra information, whose interpretation
   depends on the section type

 - If the section type is SHT_REL or SHT_RELA, the sh_info field holds
   the section header index of the section to which the relocation
   applies.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-08-03 22:58:10 +09:00
Masahiro Yamada
125ed24a4a modpost: add array range check to sec_name()
The section index is always positive, so the argument, secindex, should
be unsigned.

Also, inserted the array range check.

If sym->st_shndx is a special section index (between SHN_LORESERVE and
SHN_HIRESERVE), there is no corresponding section header.

For example, if a symbol specifies an absolute value, sym->st_shndx is
SHN_ABS (=0xfff1).

The current users do not cause the out-of-range access of
info->sechddrs[], but it is better to avoid such a pitfall.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-08-03 22:58:10 +09:00
Masahiro Yamada
36b0f0deed modpost: refactor get_secindex()
SPECIAL() is only used in get_secindex(). Squash it.

Make the code more readable with more comments.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-08-03 22:56:46 +09:00
Masahiro Yamada
7193cda917 modpost: remove unused Elf_Sword macro
Commit 9ad21c3f3e ("kbuild: try harder to find symbol names in
modpost") added Elf_Sword (in a wrong way), but did not use it at all.

BTW, the current code looks weird.

The fix for the 32-bit part would be:

    Elf64_Sword  -->  Elf32_Sword

(inconsistet prefix, Elf32_ vs Elf64_)

The fix for the 64-bit part would be:

    Elf64_Sxword  -->  Elf64_Sword

(the size is different between Sword and Sxword)

Note:

    Elf32_Sword   ==  Elf64_Sword   ==  int32_t
    Elf32_Sxword  ==  Elf64_Sxword  ==  int64_t

Anyway, let's drop unused code instead of fixing it.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2022-08-03 19:37:59 +09:00
Linus Torvalds
665fe72a7d linux-kselftest-kunit-5.20-rc1
This KUnit update for Linux 5.20-rc1 consists of several fixes and an
 important feature to discourage running KUnit tests on production
 systems. Running tests on a production system could leave the system
 in a bad state. This new feature adds:
 
 - adds a new taint type, TAINT_TEST to signal that a test has been run.
   This should discourage people from running these tests on production
   systems, and to make it easier to tell if tests have been run
   accidentally (by loading the wrong configuration, etc.)
 
 - several documentation and tool enhancements and fixes.
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Merge tag 'linux-kselftest-kunit-5.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull KUnit updates from Shuah Khan:
 "This consists of several fixes and an important feature to discourage
  running KUnit tests on production systems. Running tests on a
  production system could leave the system in a bad state.

  Summary:

   - Add a new taint type, TAINT_TEST to signal that a test has been
     run.

     This should discourage people from running these tests on
     production systems, and to make it easier to tell if tests have
     been run accidentally (by loading the wrong configuration, etc)

   - Several documentation and tool enhancements and fixes"

* tag 'linux-kselftest-kunit-5.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (29 commits)
  Documentation: KUnit: Fix example with compilation error
  Documentation: kunit: Add CLI args for kunit_tool
  kcsan: test: Add a .kunitconfig to run KCSAN tests
  kunit: executor: Fix a memory leak on failure in kunit_filter_tests
  clk: explicitly disable CONFIG_UML_PCI_OVER_VIRTIO in .kunitconfig
  mmc: sdhci-of-aspeed: test: Use kunit_test_suite() macro
  nitro_enclaves: test: Use kunit_test_suite() macro
  thunderbolt: test: Use kunit_test_suite() macro
  kunit: flatten kunit_suite*** to kunit_suite** in .kunit_test_suites
  kunit: unify module and builtin suite definitions
  selftest: Taint kernel when test module loaded
  module: panic: Taint the kernel when selftest modules load
  Documentation: kunit: fix example run_kunit func to allow spaces in args
  Documentation: kunit: Cleanup run_wrapper, fix x-ref
  kunit: test.h: fix a kernel-doc markup
  kunit: tool: Enable virtio/PCI by default on UML
  kunit: tool: make --kunitconfig repeatable, blindly concat
  kunit: add coverage_uml.config to enable GCOV on UML
  kunit: tool: refactor internal kconfig handling, allow overriding
  kunit: tool: introduce --qemu_args
  ...
2022-08-02 19:34:45 -07:00
Masahiro Yamada
abe864b8e1 modpost: use sym_get_data() to get module device_table data
Use sym_get_data() to replace the long code.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2022-07-27 21:18:00 +09:00
Masahiro Yamada
5764f6626f modpost: drop executable ELF support
Since commit 269a535ca9 ("modpost: generate vmlinux.symvers and
reuse it for the second modpost"), modpost only parses relocatable
files (ET_REL).

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2022-07-27 21:18:00 +09:00
Masahiro Yamada
028062ec22 Revert "scripts/mod/modpost.c: permit '.cranges' secton for sh64 architecture."
This reverts commit 4d10c223ba.

Commit 37744feebc ("sh: remove sh5 support") removed the sh64 support
entirely.

Note:
.cranges was only used for sh64 ever.
Commit 211dc24b8744 ("Remove sh5 and sh64 support") in binutils-gdb
already removed the relevant code.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2022-07-27 21:17:59 +09:00
David Gow
74829ddf59 module: panic: Taint the kernel when selftest modules load
Taint the kernel with TAINT_TEST whenever a test module loads, by adding
a new "TEST" module property, and setting it for all modules in the
tools/testing directory. This property can also be set manually, for
tests which live outside the tools/testing directory with:
MODULE_INFO(test, "Y");

Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Acked-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-07-11 16:58:00 -06:00
Masahiro Yamada
28438794ab modpost: fix section mismatch check for exported init/exit sections
Since commit f02e8a6596 ("module: Sort exported symbols"),
EXPORT_SYMBOL* is placed in the individual section ___ksymtab(_gpl)+<sym>
(3 leading underscores instead of 2).

Since then, modpost cannot detect the bad combination of EXPORT_SYMBOL
and __init/__exit.

Fix the .fromsec field.

Fixes: f02e8a6596 ("module: Sort exported symbols")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2022-06-20 08:18:03 +09:00
Linus Torvalds
71e80720db Kbuild updates for v5.19 (2nd)
- Fix build regressions for parisc, csky, nios2, openrisc
 
  - Simplify module builds for CONFIG_LTO_CLANG and CONFIG_X86_KERNEL_IBT
 
  - Remove arch/parisc/nm, which was presumably a workaround for old tools
 
  - Check the odd combination of EXPORT_SYMBOL and 'static' precisely
 
  - Make external module builds robust against "too long argument error"
 
  - Support j, k keys for moving the cursor in nconfig
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Merge tag 'kbuild-v5.19-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull more Kbuild updates from Masahiro Yamada:

 - Fix build regressions for parisc, csky, nios2, openrisc

 - Simplify module builds for CONFIG_LTO_CLANG and CONFIG_X86_KERNEL_IBT

 - Remove arch/parisc/nm, which was presumably a workaround for old
   tools

 - Check the odd combination of EXPORT_SYMBOL and 'static' precisely

 - Make external module builds robust against "too long argument error"

 - Support j, k keys for moving the cursor in nconfig

* tag 'kbuild-v5.19-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (25 commits)
  kbuild: Allow to select bash in a modified environment
  scripts: kconfig: nconf: make nconfig accept jk keybindings
  modpost: use fnmatch() to simplify match()
  modpost: simplify mod->name allocation
  kbuild: factor out the common objtool arguments
  kbuild: move vmlinux.o link to scripts/Makefile.vmlinux_o
  kbuild: clean .tmp_* pattern by make clean
  kbuild: remove redundant cleanups in scripts/link-vmlinux.sh
  kbuild: rebuild multi-object modules when objtool is updated
  kbuild: add cmd_and_savecmd macro
  kbuild: make *.mod rule robust against too long argument error
  kbuild: make built-in.a rule robust against too long argument error
  kbuild: check static EXPORT_SYMBOL* by script instead of modpost
  parisc: remove arch/parisc/nm
  kbuild: do not create *.prelink.o for Clang LTO or IBT
  kbuild: replace $(linked-object) with CONFIG options
  kbuild: do not try to parse *.cmd files for objects provided by compiler
  kbuild: replace $(if A,A,B) with $(or A,B) in scripts/Makefile.modpost
  modpost: squash if...else-if in find_elf_symbol2()
  modpost: reuse ARRAY_SIZE() macro for section_mismatch()
  ...
2022-06-05 09:06:03 -07:00
Masahiro Yamada
a89227d769 modpost: use fnmatch() to simplify match()
Replace the own implementation for wildcard (glob) matching with
a function call to fnmatch().

Also, change the return type to 'bool'.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-06-05 06:20:57 +09:00
Masahiro Yamada
8c9ce89c5b modpost: simplify mod->name allocation
mod->name is set to the ELF filename with the suffix ".o" stripped.

The current code calls strdup() and free() to manipulate the string,
but a simpler approach is to pass new_module() with the name length
subtracted by 2.

Also, check if the passed filename ends with ".o" before stripping it.

The current code blindly chops the suffix:

    tmp[strlen(tmp) - 2] = '\0'

It will cause buffer under-run if strlen(tmp) < 2;

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2022-06-05 06:20:57 +09:00
Linus Torvalds
6f9b5ed8ca Char / Misc / Other smaller driver subsystem updates for 5.19-rc1
Here is the large set of char, misc, and other driver subsystem updates
 for 5.19-rc1.  The merge request for this has been delayed as I wanted
 to get lots of linux-next testing due to some late arrivals of changes
 for the habannalabs driver.
 
 Highlights of this merge are:
 	- habanalabs driver updates for new hardware types and fixes and
 	  other updates
 	- IIO driver tree merge which includes loads of new IIO drivers
 	  and cleanups and additions
 	- PHY driver tree merge with new drivers and small updates to
 	  existing ones
 	- interconnect driver tree merge with fixes and updates
 	- soundwire driver tree merge with some small fixes
 	- coresight driver tree merge with small fixes and updates
 	- mhi bus driver tree merge with lots of updates and new device
 	  support
 	- firmware driver updates
 	- fpga driver updates
 	- lkdtm driver updates (with a merge conflict, more on that
 	  below)
 	- extcon driver tree merge with small updates
 	- lots of other tiny driver updates and fixes and cleanups, full
 	  details in the shortlog.
 
 All of these have been in linux-next for almost 2 weeks with no reported
 problems.
 
 Note, there are 3 merge conflicts when merging this with your tree:
 	- MAINTAINERS, should be easy to resolve
 	- drivers/slimbus/qcom-ctrl.c, should be straightforward
 	  resolution
 	- drivers/misc/lkdtm/stackleak.c, not an easy resolution.  This
 	  has been noted in the linux-next tree for a while, and
 	  resolved there, here's a link to the resolution that Stephen
 	  came up with and that Kees says is correct:
 	  	https://lore.kernel.org/r/20220509185344.3fe1a354@canb.auug.org.au
 
 I will be glad to provide a merge point that contains these resolutions
 if that makes things any easier for you.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char / misc / other smaller driver subsystem updates from Greg KH:
 "Here is the large set of char, misc, and other driver subsystem
  updates for 5.19-rc1. The merge request for this has been delayed as I
  wanted to get lots of linux-next testing due to some late arrivals of
  changes for the habannalabs driver.

  Highlights of this merge are:

   - habanalabs driver updates for new hardware types and fixes and
     other updates

   - IIO driver tree merge which includes loads of new IIO drivers and
     cleanups and additions

   - PHY driver tree merge with new drivers and small updates to
     existing ones

   - interconnect driver tree merge with fixes and updates

   - soundwire driver tree merge with some small fixes

   - coresight driver tree merge with small fixes and updates

   - mhi bus driver tree merge with lots of updates and new device
     support

   - firmware driver updates

   - fpga driver updates

   - lkdtm driver updates (with a merge conflict, more on that below)

   - extcon driver tree merge with small updates

   - lots of other tiny driver updates and fixes and cleanups, full
     details in the shortlog.

  All of these have been in linux-next for almost 2 weeks with no
  reported problems"

* tag 'char-misc-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (387 commits)
  habanalabs: use separate structure info for each error collect data
  habanalabs: fix missing handle shift during mmap
  habanalabs: remove hdev from hl_ctx_get args
  habanalabs: do MMU prefetch as deferred work
  habanalabs: order memory manager messages
  habanalabs: return -EFAULT on copy_to_user error
  habanalabs: use NULL for eventfd
  habanalabs: update firmware header
  habanalabs: add support for notification via eventfd
  habanalabs: add topic to memory manager buffer
  habanalabs: handle race in driver fini
  habanalabs: add device memory scrub ability through debugfs
  habanalabs: use unified memory manager for CB flow
  habanalabs: unified memory manager new code for CB flow
  habanalabs/gaudi: set arbitration timeout to a high value
  habanalabs: add put by handle method to memory manager
  habanalabs: hide memory manager page shift
  habanalabs: Add separate poll interval value for protocol
  habanalabs: use get_task_pid() to take PID
  habanalabs: add prefetch flag to the MAP operation
  ...
2022-06-03 11:36:34 -07:00
Masahiro Yamada
31cb50b559 kbuild: check static EXPORT_SYMBOL* by script instead of modpost
The 'static' specifier and EXPORT_SYMBOL() are an odd combination.

Commit 15bfc2348d ("modpost: check for static EXPORT_SYMBOL*
functions") tried to detect it, but this check has false negatives.

Here is the sample code.

  Makefile:

    obj-y += foo1.o foo2.o

  foo1.c:

    #include <linux/export.h>
    static void foo(void) {}
    EXPORT_SYMBOL(foo);

  foo2.c:

    void foo(void) {}

foo1.c exports the static symbol 'foo', but modpost cannot catch it
because it is fooled by foo2.c, which has a global symbol with the
same name.

s->is_static is cleared if a global symbol with the same name is found
somewhere, but EXPORT_SYMBOL() and the global symbol do not necessarily
belong to the same compilation unit.

This check should be done per compilation unit, but I do not know how
to do it in modpost. modpost runs against vmlinux.o or modules, which
merges multiple objects, then forgets their origin.

modpost cannot parse individual objects because they may not be ELF but
LLVM IR when CONFIG_LTO_CLANG=y.

Add a simple bash script to parse the output from ${NM}. This works for
CONFIG_LTO_CLANG=y because llvm-nm can dump symbols of LLVM IR files.

Revert 15bfc2348d.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14 (x86-64)
2022-06-01 23:07:02 +09:00
Masahiro Yamada
c25e1c5582 kbuild: do not create *.prelink.o for Clang LTO or IBT
When CONFIG_LTO_CLANG=y, additional intermediate *.prelink.o is created
for each module. Also, objtool is postponed until LLVM IR is converted
to ELF.

CONFIG_X86_KERNEL_IBT works in a similar way to postpone objtool until
objects are merged together.

This commit stops generating *.prelink.o, so the build flow will look
similar with/without LTO.

The following figures show how the LTO build currently works, and
how this commit is changing it.

Current build flow
==================

 [1] single-object module

                                      $(LD)
           $(CC)                     +objtool              $(LD)
    foo.c --------------------> foo.o -----> foo.prelink.o -----> foo.ko
                              (LLVM IR)          (ELF)       |    (ELF)
                                                             |
                                                 foo.mod.o --/
                                                 (LLVM IR)

 [2] multi-object module
                                      $(LD)
           $(CC)         $(AR)       +objtool               $(LD)
    foo1.c -----> foo1.o -----> foo.o -----> foo.prelink.o -----> foo.ko
                           |  (archive)          (ELF)       |    (ELF)
    foo2.c -----> foo2.o --/                                 |
                 (LLVM IR)                       foo.mod.o --/
                                                 (LLVM IR)

  One confusion is that foo.o in multi-object module is an archive
  despite of its suffix.

New build flow
==============

 [1] single-object module

  Since there is only one object, there is no need to keep the LLVM IR.
  Use $(CC)+$(LD) to generate an ELF object in one build rule. When LTO
  is disabled, $(LD) is unneeded because $(CC) produces an ELF object.

               $(CC)+$(LD)+objtool              $(LD)
    foo.c ----------------------------> foo.o ---------> foo.ko
                                        (ELF)     |      (ELF)
                                                  |
                                      foo.mod.o --/
                                      (LLVM IR)

 [2] multi-object module

  Previously, $(AR) was used to combine LLVM IR files into an archive,
  but there was no technical reason to do so. Use $(LD) to merge them
  into a single ELF object.

                               $(LD)
             $(CC)            +objtool          $(LD)
    foo1.c ---------> foo1.o ---------> foo.o ---------> foo.ko
                                 |      (ELF)     |      (ELF)
    foo2.c ---------> foo2.o ----/                |
                     (LLVM IR)        foo.mod.o --/
                                      (LLVM IR)

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14 (x86-64)
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
2022-05-29 18:39:35 +09:00
Masahiro Yamada
68fef6704e modpost: squash if...else-if in find_elf_symbol2()
if ((addr - sym->st_value) < distance) {
            distance = addr - sym->st_value;
            near = sym;
    } else if ((addr - sym->st_value) == distance) {
            near = sym;
    }

is equivalent to:

    if (addr - sym->st_value <= distance) {
            distance = addr - sym->st_value;
            near = sym;
    }

(The else-if block can overwrite 'distance' with the same value).

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2022-05-27 16:16:35 +09:00
Masahiro Yamada
c5c468dcc2 modpost: reuse ARRAY_SIZE() macro for section_mismatch()
Move ARRAY_SIZE() from file2alias.c to modpost.h to reuse it in
section_mismatch().

Also, move the variable 'check' inside the for-loop.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2022-05-27 16:15:40 +09:00
Masahiro Yamada
76954527fe modpost: remove the unused argument of check_sec_ref()
check_sec_ref() does not use the first parameter 'mod'.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2022-05-27 16:10:10 +09:00
Masahiro Yamada
d6b732666a modpost: fix undefined behavior of is_arm_mapping_symbol()
The return value of is_arm_mapping_symbol() is unpredictable when "$"
is passed in.

strchr(3) says:
  The strchr() and strrchr() functions return a pointer to the matched
  character or NULL if the character is not found. The terminating null
  byte is considered part of the string, so that if c is specified as
  '\0', these functions return a pointer to the terminator.

When str[1] is '\0', strchr("axtd", str[1]) is not NULL, and str[2] is
referenced (i.e. buffer overrun).

Test code
---------

  char str1[] = "abc";
  char str2[] = "ab";

  strcpy(str1, "$");
  strcpy(str2, "$");

  printf("test1: %d\n", is_arm_mapping_symbol(str1));
  printf("test2: %d\n", is_arm_mapping_symbol(str2));

Result
------

  test1: 0
  test2: 1

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2022-05-27 16:07:44 +09:00
Alexander Lobakin
b5beffa20d modpost: fix removing numeric suffixes
With the `-z unique-symbol` linker flag or any similar mechanism,
it is possible to trigger the following:

ERROR: modpost: "param_set_uint.0" [vmlinux] is a static EXPORT_SYMBOL

The reason is that for now the condition from remove_dot():

if (m && (s[n + m] == '.' || s[n + m] == 0))

which was designed to test if it's a dot or a '\0' after the suffix
is never satisfied.
This is due to that `s[n + m]` always points to the last digit of a
numeric suffix, not on the symbol next to it (from a custom debug
print added to modpost):

param_set_uint.0, s[n + m] is '0', s[n + m + 1] is '\0'

So it's off-by-one and was like that since 2014.

Fix this for the sake of any potential upcoming features, but don't
bother stable-backporting, as it's well hidden -- apart from that
LD flag, it can be triggered only with GCC LTO which never landed
upstream.

Fixes: fcd38ed0ff ("scripts: modpost: fix compilation warning")
Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2022-05-27 16:05:01 +09:00
Masahiro Yamada
7b4537199a kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS
include/{linux,asm-generic}/export.h defines a weak symbol, __crc_*
as a placeholder.

Genksyms writes the version CRCs into the linker script, which will be
used for filling the __crc_* symbols. The linker script format depends
on CONFIG_MODULE_REL_CRCS. If it is enabled, __crc_* holds the offset
to the reference of CRC.

It is time to get rid of this complexity.

Now that modpost parses text files (.*.cmd) to collect all the CRCs,
it can generate C code that will be linked to the vmlinux or modules.

Generate a new C file, .vmlinux.export.c, which contains the CRCs of
symbols exported by vmlinux. It is compiled and linked to vmlinux in
scripts/link-vmlinux.sh.

Put the CRCs of symbols exported by modules into the existing *.mod.c
files. No additional build step is needed for modules. As before,
*.mod.c are compiled and linked to *.ko in scripts/Makefile.modfinal.

No linker magic is used here. The new C implementation works in the
same way, whether CONFIG_RELOCATABLE is enabled or not.
CONFIG_MODULE_REL_CRCS is no longer needed.

Previously, Kbuild invoked additional $(LD) to update the CRCs in
objects, but this step is unneeded too.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nicolas Schier <nicolas@fjasle.eu>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14 (x86-64)
2022-05-24 16:33:20 +09:00
Masahiro Yamada
f292d875d0 modpost: extract symbol versions from *.cmd files
Currently, CONFIG_MODVERSIONS needs extra link to embed the symbol
versions into ELF objects. Then, modpost extracts the version CRCs
from them.

The following figures show how it currently works, and how I am trying
to change it.

Current implementation
======================
                                                           |----------|
                 embed CRC      -------------------------->| final    |
       $(CC)       $(LD)       /  |---------|              | link for |
       -----> *.o -------> *.o -->| modpost |              | vmlinux  |
      /              /            |         |-- *.mod.c -->| or       |
     / genksyms     /             |---------|              | module   |
  *.c ------> *.symversions                                |----------|

Genksyms outputs the calculated CRCs in the form of linker script
(*.symversions), which is used by $(LD) to update the object.

If CONFIG_LTO_CLANG=y, the build process is much more complex. Embedding
the CRCs is postponed until the LLVM bitcode is converted into ELF,
creating another intermediate *.prelink.o.

However, this complexity is unneeded. There is no reason why we must
embed version CRCs in objects so early.

There is final link stage for vmlinux (scripts/link-vmlinux.sh) and
modules (scripts/Makefile.modfinal). We can link CRCs at the very last
moment.

New implementation
==================
                                                           |----------|
                   --------------------------------------->| final    |
       $(CC)      /    |---------|                         | link for |
       -----> *.o ---->|         |                         | vmlinux  |
      /                | modpost |--- .vmlinux.export.c -->| or       |
     / genksyms        |         |--- *.mod.c ------------>| module   |
  *.c ------> *.cmd -->|---------|                         |----------|

Pass the symbol versions to modpost as separate text data, which are
available in *.cmd files.

This commit changes modpost to extract CRCs from *.cmd files instead of
from ELF objects.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14 (x86-64)
2022-05-24 00:53:06 +09:00
Masahiro Yamada
69c4cc99bb modpost: add sym_find_with_module() helper
find_symbol() returns the first symbol found in the hash table. This
table is global, so it may return a symbol from an unexpected module.

There is a case where we want to search for a symbol with a given name
in a specified module.

Add sym_find_with_module(), which receives the module pointer as the
second argument. It is equivalent to find_module() if NULL is passed
as the module pointer.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM-14 (x86-64)
2022-05-24 00:52:12 +09:00
Masahiro Yamada
2a66c3124a modpost: change the license of EXPORT_SYMBOL to bool type
There were more EXPORT_SYMBOL types in the past. The following commits
removed unused ones.

 - f1c3d73e97 ("module: remove EXPORT_SYMBOL_GPL_FUTURE")
 - 367948220f ("module: remove EXPORT_UNUSED_SYMBOL*")

There are 3 remaining in enum export, but export_unknown does not make
any sense because we never expect such a situation like "we do not know
how it was exported".

If the symbol name starts with "__ksymtab_", but the section name
does not start with "___ksymtab+" or "___ksymtab_gpl+", it is not an
exported symbol.

It occurs when a variable starting with "__ksymtab_" is directly defined:

   int __ksymtab_foo;

Presumably, there is no practical issue for using such a weird variable
name (but there is no good reason for doing so, either).

Anyway, that is not an exported symbol. Setting export_unknown is not
the right thing to do. Do not call sym_add_exported() in this case.

With pointless export_unknown removed, the export type finally becomes
boolean (either EXPORT_SYMBOL or EXPORT_SYMBOL_GPL).

I renamed the field name to is_gpl_only. EXPORT_SYMBOL_GPL sets it true.
Only GPL-compatible modules can use it.

I removed the orphan comment, "How a symbol is exported", which is
unrelated to sec_mismatch_count. It is about enum export.
See commit bd5cbcedf4 ("kbuild: export-type enhancement to modpost.c")

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Tested-by: Nathan Chancellor <nathan@kernel.org>
2022-05-11 21:46:39 +09:00