Hi!
The second patch of this series caused some troubles on 5.15.y, I apologize about it [1]. When I tested it locally, I needed to set CONFIG_LIVEPATCH, so kallsyms_on_each_symbol() would be known at link time. To cope with this problem, we need to backport the first patch of this series as pointed by Guenter Roeck [2]. This patch is only needed for 5.15, indeed the dependencies on CONFIG_LIVEPATCH for kallsyms_on_each_symbol() was added in 3e3552056ab4 ("kallsyms: only build {,module_}kallsyms_on_each_symbol when required"). This commit was first added to kernel 5.12, as git indicates it: $ git name-rev --tags --name-only 3e3552056ab4 v5.12-rc1~67^2~8 Moreover, the first patch of this series, i.e. d721def7392a ("kallsyms: Make kallsyms_on_each_symbol generally available") was first added in: $ git name-rev --tags --name-only d721def7392a v5.19-rc1~159^2~4^2~38^2~4 So, my patch only needs the first patch for the 5.15 kernel.
Regarding these two patches, I built and tested the series for several architectures: * i386: $ make ARCH=i386 defconfig kvm_guest.config ... $ make ARCH=i386 -j$(nproc) ... Kernel: arch/x86/boot/bzImage is ready (#1) $ bash run_extern_kernel.sh i386 ... root@vm-i386:~# uname -mr 5.15.140+ i686 root@vm-i386:~# echo 'p:myprobe name_show' > /sys/kernel/tracing/kprobe_events -bash: echo: write error: Cannot assign requested address * x86_64: $ make x86_64_defconfig kvm_guest.config ... $ make -j$(nproc) ... Kernel: arch/x86/boot/bzImage is ready (#9) $ bash run_extern_kernel.sh ... root@vm-amd64:~# uname -rm 5.15.140+ x86_64 root@vm-amd64:~# echo 'p:myprobe name_show' > /sys/kernel/tracing/kprobe_events -bash: echo: write error: Cannot assign requested address * arm: $ make ARCH=arm defconfig kvm_guest.config ... $ make ARCH=arm menuconfig # Add CONFIG_KPROBES $ make ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- -j$(nproc) ... Kernel: arch/arm/boot/zImage is ready $ bash run_extern_kernel.sh armel ... root@vm-armel:~# uname -mr 5.15.140-00002-gd3fdc3ca50b5 armv7l root@vm-armel:~# echo 'p:myprobe name_show' > /sys/kernel/tracing/kprobe_events -bash: echo: write error: Cannot assign requested address * arm64: $ make ARCH=arm64 defconfig kvm_guest.config # Add CONFIG_KPROBES ... $ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- -j$(nproc) ... OBJCOPY arch/arm64/boot/Image GZIP arch/arm64/boot/Image.gz $ bash run_extern_kernel.sh arm64 ... root@vm-arm64:~# uname -mr 5.15.140-00002-gd3fdc3ca50b5 aarch64 root@vm-arm64:~# echo 'p:myprobe name_show' > /sys/kernel/tracing/kprobe_events -bash: echo: write error: Cannot assign requested address
If you see any ways to improve this patch, please share your feedback.
Francis Laniel (1): tracing/kprobes: Return EADDRNOTAVAIL when func matches several symbols
Jiri Olsa (1): kallsyms: Make kallsyms_on_each_symbol generally available
include/linux/kallsyms.h | 7 +++- kernel/kallsyms.c | 2 - kernel/trace/trace_kprobe.c | 74 +++++++++++++++++++++++++++++++++++++ kernel/trace/trace_probe.h | 1 + 4 files changed, 81 insertions(+), 3 deletions(-)
Best regards. --- [1]: https://lore.kernel.org/stable/CAEUSe78tYPTFuauB7cxZzvAeMhzB_25Q8DqLUfF7Nro9... [2]: https://lore.kernel.org/stable/06deae26-c59c-4746-867d-ab6f5852b0af@roeck-us... -- 2.34.1