Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> writes: > Hi Michael, > > On Mon, Jun 28, 2021 at 1:00 AM Michael Schmitz <schmitzmic@xxxxxxxxx> wrote: >> On 28/06/21 10:13 am, Al Viro wrote: >> > On Thu, Jun 24, 2021 at 10:45:23PM +0000, Al Viro wrote: >> > >> >> 13) there's bdflush(1, whatever), which is equivalent to exit(0). >> >> IMO it's long past the time to simply remove the sucker. >> > Incidentally, calling that from ptraced process on alpha leads to >> > the same headache for tracer. _If_ we leave it around, this is >> > another candidate for "hit yourself with that special signal" - >> > both alpha and m68k have that syscall, and IMO adding an asm >> > wrapper for that one is over the top. >> > >> > Said that, we really ought to bury that thing: >> > >> > commit 2f268ee88abb33968501a44368db55c63adaad40 >> > Author: Andrew Morton <akpm@xxxxxxxxx> >> > Date: Sat Dec 14 03:16:29 2002 -0800 >> > >> > [PATCH] deprecate use of bdflush() >> > >> > Patch from Robert Love <rml@xxxxxxxxx> >> > >> > We can never get rid of it if we do not deprecate it - so do so and >> > print a stern warning to those who still run bdflush daemons. >> > >> > Deprecated for 18.5 years by now - I seriously suspect that we have >> > some contributors younger than that... >> >> Haven't found that warning in over 7 years' worth of console logs, and >> I'm a good candidate for running the oldest userland in existence for m68k. >> >> Time to let it go. > > The warning is printed when using filesys-ELF-2.0.x-1400K-2.gz, > which is a very old ramdisk from right after the m68k a.out to ELF > transition: > > warning: process `update' used the obsolete bdflush system call > Fix your initscripts? > > I still boot it, once in a while. The only thing left in bdflush is func == 1 calls do_exit(0); Which is a hack introduced in 2.3.23 aka October of 1999 to force the userspace process calling bdflush to exit, instead of repeatedly calling sys_bdflush. Can you try deleting that func == 1 call and seeing if your old ramdisk works? I suspect userspace used to get into a tight spin calling bdflush func == 1, when that function stopped doing anything. That was back in 1999 so we are probably safe with out it. Eric
