f54708e4a2
commit efbd6398353315b7018e6943e41fee9ec35e875f upstream. GNU's addr2line can have problems parsing a vmlinux built with LLVM, particularly when LTO was used. In order to decode the traces correctly this patch adds the ability to switch to LLVM's utilities readelf and addr2line. The same approach is followed by Will in [1]. Before: $ scripts/decode_stacktrace.sh vmlinux < kernel.log [17716.240635] Call trace: [17716.240646] skb_cow_data (??:?) [17716.240654] esp6_input (ld-temp.o:?) [17716.240666] xfrm_input (ld-temp.o:?) [17716.240674] xfrm6_rcv (??:?) [...] After: $ LLVM=1 scripts/decode_stacktrace.sh vmlinux < kernel.log [17716.240635] Call trace: [17716.240646] skb_cow_data (include/linux/skbuff.h:2172 net/core/skbuff.c:4503) [17716.240654] esp6_input (net/ipv6/esp6.c:977) [17716.240666] xfrm_input (net/xfrm/xfrm_input.c:659) [17716.240674] xfrm6_rcv (net/ipv6/xfrm6_input.c:172) [...] Note that one could set CROSS_COMPILE=llvm- instead to hack around this issue. However, doing so can break the decodecode routine as it will force the selection of other LLVM utilities down the line e.g. llvm-as. [1] https://lore.kernel.org/all/20230914131225.13415-3-will@kernel.org/ Link: https://lkml.kernel.org/r/20230929034836.403735-1-cmllamas@google.com Signed-off-by: Carlos Llamas <cmllamas@google.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Elliot Berman <quic_eberman@quicinc.com> Tested-by: Justin Stitt <justinstitt@google.com> Cc: Will Deacon <will@kernel.org> Cc: John Stultz <jstultz@google.com> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Tom Rix <trix@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 Restructured Text 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.