From mboxrd@z Thu Jan 1 00:00:00 1970 From: Baoquan He Date: Thu, 19 May 2022 10:58:19 +0800 Subject: [PATCH] kexec_file: Drop weak attribute from arch_kexec_apply_relocations[_add] In-Reply-To: <87ee0q7b92.fsf@email.froward.int.ebiederm.org> References: <20220518181828.645877-1-naveen.n.rao@linux.vnet.ibm.com> <87ee0q7b92.fsf@email.froward.int.ebiederm.org> Message-ID: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: kexec@lists.infradead.org Hi Eric, On 05/18/22 at 04:59pm, Eric W. Biederman wrote: > "Naveen N. Rao" writes: > > > Since commit d1bcae833b32f1 ("ELF: Don't generate unused section > > symbols") [1], binutils (v2.36+) started dropping section symbols that > > it thought were unused. This isn't an issue in general, but with > > kexec_file.c, gcc is placing kexec_arch_apply_relocations[_add] into a > > separate .text.unlikely section and the section symbol ".text.unlikely" > > is being dropped. Due to this, recordmcount is unable to find a non-weak > > symbol in .text.unlikely to generate a relocation record against. > > > > Address this by dropping the weak attribute from these functions: > > - arch_kexec_apply_relocations() is not overridden by any architecture > > today, so just drop the weak attribute. > > - arch_kexec_apply_relocations_add() is only overridden by x86 and s390. > > Retain the function prototype for those and move the weak > > implementation into the header as a static inline for other > > architectures. > > > > [1] https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=d1bcae833b32f1 > > Any chance you can also get machine_kexec_post_load, > crash_free_reserved_phys_range, arch_kexec_protect_protect_crashkres, > arch_kexec_unprotect_crashkres, arch_kexec_kernel_image_probe, > arch_kexec_kernel_image_probe, arch_kimage_file_post_load_cleanup, > arch_kexec_kernel_verify_sig, and arch_kexec_locate_mem_hole as well. > > That is everything in kexec that uses a __weak symbol. If we can't > count on them working we might as well just get rid of the rest > preemptively. Is there a new rule that __weak is not suggested in kernel any more? Please help provide a pointer if yes, so that I can learn that. In my mind, __weak is very simple and clear as a mechanism to add ARCH related functionality. Thanks Baoquan