parisc: use generic sys_fanotify_mark implementation
The sys_fanotify_mark() syscall on parisc uses the reverse word order for the two halves of the 64-bit argument compared to all syscalls on all 32-bit architectures. As far as I can tell, the problem is that the function arguments on parisc are sorted backwards (26, 25, 24, 23, ...) compared to everyone else, so the calling conventions of using an even/odd register pair in native word order result in the lower word coming first in function arguments, matching the expected behavior on little-endian architectures. The system call conventions however ended up matching what the other 32-bit architectures do. A glibc cleanup in 2020 changed the userspace behavior in a way that handles all architectures consistently, but this inadvertently broke parisc32 by changing to the same method as everyone else. The change made it into glibc-2.35 and subsequently into debian 12 (bookworm), which is the latest stable release. This means we need to choose between reverting the glibc change or changing the kernel to match it again, but either hange will leave some systems broken. Pick the option that is more likely to help current and future users and change the kernel to match current glibc. This also means the behavior is now consistent across architectures, but it breaks running new kernels with old glibc builds before 2.35. Link: https://sourceware.org/git/?p=glibc.git;a=commitdiff;h=d150181d73d9 Link: https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/commit/arch/parisc/kernel/sys_parisc.c?h=57b1dfbd5b4a39d Cc: Adhemerval Zanella <adhemerval.zanella@linaro.org> Tested-by: Helge Deller <deller@gmx.de> Acked-by: Helge Deller <deller@gmx.de> Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- I found this through code inspection, please double-check to make sure I got the bug and the fix right. The alternative is to fix this by reverting glibc back to the unusual behavior.
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