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Lorenz Bauer 2e2713ae1a btf: Fix virt_to_phys() on arm64 when mmapping BTF
Breno Leitao reports that arm64 emits the following warning
with CONFIG_DEBUG_VIRTUAL:

    [   58.896157] virt_to_phys used for non-linear address: 000000009fea9737
      (__start_BTF+0x0/0x685530)
    [   23.988669] WARNING: CPU: 25 PID: 1442 at arch/arm64/mm/physaddr.c:15
      __virt_to_phys (arch/arm64/mm/physaddr.c:?)

        ...

    [   24.075371] Tainted: [E]=UNSIGNED_MODULE, [N]=TEST
    [   24.080276] Hardware name: Quanta S7GM 20S7GCU0010/S7G MB (CG1), BIOS 3D22
      07/03/2024
    [   24.088295] pstate: 63400009 (nZCv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
    [   24.098440] pc : __virt_to_phys (arch/arm64/mm/physaddr.c:?)
    [   24.105398] lr : __virt_to_phys (arch/arm64/mm/physaddr.c:?)

	...

    [   24.197257] Call trace:
    [   24.199761] __virt_to_phys (arch/arm64/mm/physaddr.c:?) (P)
    [   24.206883] btf_sysfs_vmlinux_mmap (kernel/bpf/sysfs_btf.c:27)
    [   24.214264] sysfs_kf_bin_mmap (fs/sysfs/file.c:179)
    [   24.218536] kernfs_fop_mmap (fs/kernfs/file.c:462)
    [   24.222461] mmap_region (./include/linux/fs.h:? mm/internal.h:167
       mm/vma.c:2405 mm/vma.c:2467 mm/vma.c:2622 mm/vma.c:2692)

It seems that the memory layout on arm64 maps the kernel image in vmalloc space
which is different than x86. This makes virt_to_phys emit the warning.

Fix this by translating the address using __pa_symbol as suggested by
Breno instead.

Reported-by: Breno Leitao <leitao@debian.org>
Closes: https://lore.kernel.org/bpf/g2gqhkunbu43awrofzqb4cs4sxkxg2i4eud6p4qziwrdh67q4g@mtw3d3aqfgmb/
Signed-off-by: Lorenz Bauer <lmb@isovalent.com>
Tested-by: Breno Leitao <leitao@debian>
Fixes: a539e2a6d5 ("btf: Allow mmap of vmlinux btf")
Link: https://lore.kernel.org/r/20250717-vmlinux-mmap-pa-symbol-v1-1-970be6681158@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-07-17 11:33:52 -07:00
arch s390/bpf: Fix bpf_arch_text_poke() with new_addr == NULL again 2025-07-16 18:32:31 -07:00
block block-6.16-20250626 2025-06-27 09:02:33 -07:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto crypto: wp512 - Use API partial block handling 2025-06-23 16:56:56 +08:00
Documentation TTY/Serial driver fixes for 6.16-rc4 2025-06-29 09:21:27 -07:00
drivers RTC fixes for 6.16 2025-06-30 08:27:38 -07:00
fs six smb3 client fixes 2025-06-27 20:38:05 -07:00
include - Make sure the new futex phash is not copied during fork in order to 2025-06-29 08:09:13 -07:00
init init: fix build warnings about export.h 2025-06-11 22:42:36 -07:00
io_uring io_uring-6.16-20250630 2025-06-30 16:32:43 -07:00
ipc - The 3 patch series "hung_task: extend blocking task stacktrace dump to 2025-05-31 19:12:53 -07:00
kernel btf: Fix virt_to_phys() on arm64 when mmapping BTF 2025-07-17 11:33:52 -07:00
lib 16 hotfixes. 6 are cc:stable and the remainder address post-6.15 issues 2025-06-27 20:34:10 -07:00
LICENSES LICENSES: add CC0-1.0 license text 2025-05-21 14:54:17 +02:00
mm mm/damon/sysfs-schemes: free old damon_sysfs_scheme_filter->memcg_path on write 2025-06-25 15:55:03 -07:00
net Including fixes from bluetooth and wireless. 2025-06-26 09:13:27 -07:00
rust Driver core fixes for 6.16-rc3 2025-06-18 14:31:16 -07:00
samples - The 3 patch series "hung_task: extend blocking task stacktrace dump to 2025-05-31 19:12:53 -07:00
scripts scripts/gdb: fix dentry_name() lookup 2025-06-25 15:55:03 -07:00
security selinux: change security_compute_sid to return the ssid or tsid on match 2025-06-19 16:13:16 -04:00
sound ALSA: hda/realtek: Fix built-in mic on ASUS VivoBook X507UAR 2025-06-26 08:02:44 +02:00
tools selftests/bpf: Stress test attaching a BPF prog to another BPF prog 2025-07-16 18:32:31 -07:00
usr usr/include: openrisc: don't HDRTEST bpf_perf_event.h 2025-05-12 15:03:17 +09:00
virt Merge branch 'kvm-lockdep-common' into HEAD 2025-05-28 06:29:17 -04:00
.clang-format Linux 6.15-rc5 2025-05-06 16:39:25 +10:00
.clippy.toml rust: clean Rust 1.88.0's warning about clippy::disallowed_macros configuration 2025-05-07 00:11:47 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: Retire Ralf Baechle 2024-11-12 15:48:59 +01:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore .gitignore: ignore Python compiled bytecode 2025-04-24 10:12:46 -06:00
.mailmap 16 hotfixes. 6 are cc:stable and the remainder address post-6.15 issues 2025-06-27 20:34:10 -07:00
.pylintrc docs: add a .pylintrc file with sys path for docs scripts 2025-04-09 12:10:33 -06:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS CREDITS: Add entry for Shannon Nelson 2025-06-21 07:34:28 -07:00
Kbuild drm: ensure drm headers are self-contained and pass kernel-doc 2025-02-12 10:44:43 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS i2c-for-6.16-rc4 2025-06-28 15:23:17 -07:00
Makefile Linux 6.16-rc4 2025-06-29 13:09:04 -07:00
README README: Fix spelling 2024-03-18 03:36:32 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.