On Wed 2019-02-20 12:37:54, chenzefeng (A) wrote:
> On x86-64, for 32-bit PC-relacive branches, we can generate PLT32 relocation, instead of PC32 relocation. and R_X86_64_PLT32 can be treated the same as R_X86_64_PC32 since linux kernel doesn't use PLT.
>
> commit b21ebf2fb4cd ("x86: Treat R_X86_64_PLT32 as R_X86_64_PC32") been fixed for the module loading, but not fixed for livepatch relocation, which will fail to load livepatch with the error message as follow:
> relocation failed for symbol <symbol name> at <symbol address>
>
> This issue only effacted the kernel version from 4.0 to 4.6, becauce the function klp_write_module_reloc is introduced by:
> commit b700e7f03df5 ("livepatch: kernel: add support for live patching") and deleted by: commit 425595a7fc20
> ("livepatch: reuse module loader code to write relocations")
>
> Signed-off-by: chenzefeng <chenzefeng2@xxxxxxxxxx>
The patch looks fine for the 4.4 stable kernel:
Reviewed-by: Petr Mladek <pmladek@xxxxxxxx>
Best Regards,
Petr
