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Andrew Donnellan 90fb514a16 gcc-plugins: Undefine LATENT_ENTROPY_PLUGIN when plugin disabled for a file
commit 012e8d2034 upstream.

Commit 36d4b36b69 ("lib/nodemask: inline next_node_in() and
node_random()") refactored some code by moving node_random() from
lib/nodemask.c to include/linux/nodemask.h, thus requiring nodemask.h to
include random.h, which conditionally defines add_latent_entropy()
depending on whether the macro LATENT_ENTROPY_PLUGIN is defined.

This broke the build on powerpc, where nodemask.h is indirectly included
in arch/powerpc/kernel/prom_init.c, part of the early boot machinery that
is excluded from the latent entropy plugin using
DISABLE_LATENT_ENTROPY_PLUGIN. It turns out that while we add a gcc flag
to disable the actual plugin, we don't undefine LATENT_ENTROPY_PLUGIN.

This leads to the following:

    CC      arch/powerpc/kernel/prom_init.o
  In file included from ./include/linux/nodemask.h:97,
                   from ./include/linux/mmzone.h:17,
                   from ./include/linux/gfp.h:7,
                   from ./include/linux/xarray.h:15,
                   from ./include/linux/radix-tree.h:21,
                   from ./include/linux/idr.h:15,
                   from ./include/linux/kernfs.h:12,
                   from ./include/linux/sysfs.h:16,
                   from ./include/linux/kobject.h:20,
                   from ./include/linux/pci.h:35,
                   from arch/powerpc/kernel/prom_init.c:24:
  ./include/linux/random.h: In function 'add_latent_entropy':
  ./include/linux/random.h:25:46: error: 'latent_entropy' undeclared (first use in this function); did you mean 'add_latent_entropy'?
     25 |         add_device_randomness((const void *)&latent_entropy, sizeof(latent_entropy));
        |                                              ^~~~~~~~~~~~~~
        |                                              add_latent_entropy
  ./include/linux/random.h:25:46: note: each undeclared identifier is reported only once for each function it appears in
  make[2]: *** [scripts/Makefile.build:249: arch/powerpc/kernel/prom_init.o] Fehler 1
  make[1]: *** [scripts/Makefile.build:465: arch/powerpc/kernel] Fehler 2
  make: *** [Makefile:1855: arch/powerpc] Error 2

Change the DISABLE_LATENT_ENTROPY_PLUGIN flags to undefine
LATENT_ENTROPY_PLUGIN for files where the plugin is disabled.

Cc: Yury Norov <yury.norov@gmail.com>
Fixes: 38addce8b6 ("gcc-plugins: Add latent_entropy plugin")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216367
Link: https://lore.kernel.org/linuxppc-dev/alpine.DEB.2.22.394.2208152006320.289321@ramsan.of.borg/
Reported-by: Erhard Furtner <erhard_f@mailbox.org>
Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com>
Reviewed-by: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220816051720.44108-1-ajd@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-25 11:18:31 +02:00
arch powerpc/pci: Fix get_phb_number() locking 2022-08-25 11:18:29 +02:00
block blk-mq: don't create hctx debugfs dir until q->debugfs_dir is created 2022-08-25 11:17:36 +02:00
certs certs/blacklist_hashes.c: fix const confusion in certs blacklist 2022-06-22 14:11:22 +02:00
crypto crypto: drbg - make reseeding from get_random_bytes() synchronous 2022-06-22 14:11:18 +02:00
Documentation dt-bindings: arm: qcom: fix MSM8916 MTP compatibles 2022-08-25 11:18:25 +02:00
drivers igb: Add lock to avoid data race 2022-08-25 11:18:30 +02:00
fs NFSv4/pnfs: Fix a use-after-free bug in open 2022-08-25 11:18:22 +02:00
include KVM: Add infrastructure and macro to mark VM as bugged 2022-08-25 11:18:16 +02:00
init random: handle latent entropy and command line from random_init() 2022-06-22 14:11:17 +02:00
ipc ipc/mqueue: use get_tree_nodev() in mqueue_get_tree() 2022-06-14 18:11:41 +02:00
kernel tracing: Have filter accept "common_cpu" to be consistent 2022-08-25 11:18:19 +02:00
lib locking/refcount: Consolidate implementations of refcount_t 2022-07-29 17:14:17 +02:00
LICENSES
mm mm/mmap.c: fix missing call to vm_unacct_memory in mmap_region 2022-08-25 11:17:58 +02:00
net netfilter: nf_tables: really skip inactive sets when allocating name 2022-08-25 11:18:29 +02:00
samples samples/kretprobes: Fix return value if register_kretprobe() failed 2021-11-17 09:48:39 +01:00
scripts gcc-plugins: Undefine LATENT_ENTROPY_PLUGIN when plugin disabled for a file 2022-08-25 11:18:31 +02:00
security apparmor: Fix memleak in aa_simple_write_to_buffer() 2022-08-25 11:18:21 +02:00
sound ALSA: info: Fix llseek return value when using callback 2022-08-25 11:18:18 +02:00
tools tools build: Switch to new openssl API for test-libcrypto 2022-08-25 11:18:25 +02:00
usr initramfs: restore default compression behavior 2020-04-08 09:08:38 +02:00
virt KVM: Add infrastructure and macro to mark VM as bugged 2022-08-25 11:18:16 +02:00
.clang-format
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS MAINTAINERS: co-maintain random.c 2022-06-22 14:11:05 +02:00
Makefile Makefile: link with -z noexecstack --no-warn-rwx-segments 2022-08-25 11:17:17 +02:00
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