On Wed, Nov 25, 2020 at 02:56:54PM -0800, Minchan Kim wrote: > With 5.9 kernel on ARM64, I found ftrace_dump output was broken but > it had no problem with normal output "cat /sys/kernel/debug/tracing/trace". > > With investigation, it seems coping the data into temporal buffer seems to > break the align binary printf expects if the static buffer is not aligned > with 4-byte. IIUC, get_arg in bstr_printf expects that args has already > right align to be decoded and seq_buf_bprintf says ``the arguments are saved > in a 32bit word array that is defined by the format string constraints``. > So if we don't keep the align under copy to temporal buffer, the output > will be broken by shifting some bytes. > > This patch fixes it. Does this resolve the issue reported at: https://lore.kernel.org/r/20201124223917.795844-1-elavila@xxxxxxxxxx ? thanks, greg k-h
