Fix epoll_create1 flag register in my_syscall handling#3507
Merged
ptitSeb merged 1 commit intoptitSeb:mainfrom Feb 13, 2026
Merged
Fix epoll_create1 flag register in my_syscall handling#3507ptitSeb merged 1 commit intoptitSeb:mainfrom
ptitSeb merged 1 commit intoptitSeb:mainfrom
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In `my_syscall`, which handles the C ABI `syscall()` wrapper from libc, the registers are mapped according to the C calling convention: the syscall number is in `RDI` (S_EDI), and the first actual syscall argument is in `RSI` (S_ESI). For `epoll_create1` (syscall 291), the `#ifndef NOALIGN` fallback code was incorrectly passing `S_EDI` to `of_convert()`. This meant the syscall number itself (291) was being treated as the `flags` argument and passed through bitwise conversion, resulting in invalid flags being sent to the host's `epoll_create1`.
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In
my_syscall, which handles the C ABIsyscall()wrapper from libc, the registers are mapped according to the C calling convention: the syscall number is inRDI(S_EDI), and the first actual syscall argument is inRSI(S_ESI).For
epoll_create1(syscall 291), the#ifndef NOALIGNfallback code was incorrectly passingS_EDItoof_convert(). This meant the syscall number itself (291) was being treated as theflagsargument and passed through bitwise conversion, resulting in invalid flags being sent to the host'sepoll_create1.