On Fri, Mar 11, 2022 at 08:59:05PM +0530, Charan Teja Kalla wrote: > The process_madvise() system call returns error even after processing > some VMA's passed in the 'struct iovec' vector list which leaves the > user confused to know where to restart the advise next. It is also > against this syscall man page[1] documentation where it mentions that > "return value may be less than the total number of requested bytes, if > an error occurred after some iovec elements were already processed.". > > Consider a user passed 10 VMA's in the 'struct iovec' vector list of > which 9 are processed but one. Then it just returns the error caused on > that failed VMA despite the first 9 VMA's processed, leaving the user > confused about on which VMA it is failed. Returning the number of bytes > processed here can help the user to know which VMA it is failed on and > thus can retry/skip the advise on that VMA. > > [1]https://man7.org/linux/man-pages/man2/process_madvise.2.html. > > Fixes: ecb8ac8b1f14("mm/madvise: introduce process_madvise() syscall: an external memory hinting API") > Cc: <stable@xxxxxxxxxxxxxxx> # 5.10+ > Signed-off-by: Charan Teja Kalla <quic_charante@xxxxxxxxxxx> Acked-by: Minchan Kim <minchan@xxxxxxxxxx>
