diff options
| author |   Josh Poimboeuf <jpoimboe@redhat.com> | 2017-11-16 11:45:37 -0600 |
|---|---|---|
| committer |   Michael Ellerman <mpe@ellerman.id.au> | 2017-12-11 13:03:29 +1100 |
| commit | b9eab08d012fa093947b230f9a87257c27fb829b (patch) | |
| tree | fa5f33c519c97d9cbbf59b4598a8fdf8e8f4d273 /arch/powerpc/include/asm/code-patching.h | |
| parent | powerpc/modules: Add REL24 relocation support of livepatch symbols (diff) | |
| download | wireguard-linux-b9eab08d012fa093947b230f9a87257c27fb829b.tar.xz wireguard-linux-b9eab08d012fa093947b230f9a87257c27fb829b.zip | |
powerpc/modules: Don't try to restore r2 after a sibling call
When attempting to load a livepatch module, I got the following error:
module_64: patch_module: Expect noop after relocate, got 3c820000
The error was triggered by the following code in
unregister_netdevice_queue():
14c: 00 00 00 48 b 14c <unregister_netdevice_queue+0x14c>
14c: R_PPC64_REL24 net_set_todo
150: 00 00 82 3c addis r4,r2,0
GCC didn't insert a nop after the branch to net_set_todo() because it's
a sibling call, so it never returns. The nop isn't needed after the
branch in that case.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-and-tested-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/include/asm/code-patching.h')
| -rw-r--r-- | arch/powerpc/include/asm/code-patching.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/code-patching.h b/arch/powerpc/include/asm/code-patching.h index abef812de7f8..2c895e8d07f7 100644 --- a/arch/powerpc/include/asm/code-patching.h +++ b/arch/powerpc/include/asm/code-patching.h @@ -33,6 +33,7 @@ int patch_branch(unsigned int *addr, unsigned long target, int flags); int patch_instruction(unsigned int *addr, unsigned int instr); int instr_is_relative_branch(unsigned int instr); +int instr_is_relative_link_branch(unsigned int instr); int instr_is_branch_to_addr(const unsigned int *instr, unsigned long addr); unsigned long branch_target(const unsigned int *instr); unsigned int translate_branch(const unsigned int *dest, |