This issue only occurs in 5.4 LTS versions after LTS 5.4.250 (inclusive), and this patchset is based on commit 6e1f54a4985b63bc1b55a09e5e75a974c5d6719b (Linux 5.4.269)
On 2/26/24 5:49 PM, Rui Qi wrote:
Since kernel version 5.4.250 LTS, there has been an issue with the kernel live patching feature becoming unavailable. When compiling the sample code for kernel live patching, the following message is displayed when enabled:
livepatch: klp_check_stack: kworker/u256:6:23490 has an unreliable stack
After investigation, it was found that this is due to objtool not supporting intra-function calls, resulting in incorrect orc entry generation.
This patchset adds support for intra-function calls, allowing the kernel live patching feature to work correctly.
Alexandre Chartre (2): objtool: is_fentry_call() crashes if call has no destination objtool: Add support for intra-function calls
Rui Qi (1): x86/speculation: Support intra-function call validation
arch/x86/include/asm/nospec-branch.h | 7 ++ include/linux/frame.h | 11 ++++ .../Documentation/stack-validation.txt | 8 +++ tools/objtool/arch/x86/decode.c | 6 ++ tools/objtool/check.c | 64 +++++++++++++++++-- 5 files changed, 91 insertions(+), 5 deletions(-)