mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-04-02 04:41:10 -04:00
11d45eee9f
The bpf_throw() function never returns, if it has clobbered any callee-saved register, those will remain clobbered. The prologue must take care of saving all callee-saved registers in the frame of exception boundary program. Later these additional non volatile registers R14-R25 along with other NVRs are restored back in the epilogue of exception callback. To achieve above objective, the frame size is determined dynamically to accommodate additional non volatile registers in exception boundary's frame. For non-exception boundary program, the frame size remains optimal. The additional instructions to save & restore r14-r25 registers are emitted only during exception boundary and exception callback program respectively. Signed-off-by: Abhishek Dubey <adubey@linux.ibm.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Link: https://patch.msgid.link/20260124075223.6033-7-adubey@linux.ibm.com