> -----Original Message----- > From: linux-raid-owner@xxxxxxxxxxxxxxx [mailto:linux-raid- > owner@xxxxxxxxxxxxxxx] On Behalf Of Hawrylewicz Czarnowski, Przemyslaw > Sent: Thursday, December 02, 2010 12:42 AM > To: Neil Brown > Cc: linux-raid@xxxxxxxxxxxxxxx; Labun, Marcin; Czarnowska, Anna; Neubauer, > Wojciech; Williams, Dan J; Ciechanowski, Ed > Subject: RE: md as module cannot be reloaded. > > > -----Original Message----- > > From: linux-raid-owner@xxxxxxxxxxxxxxx [mailto:linux-raid- > > owner@xxxxxxxxxxxxxxx] On Behalf Of Neil Brown > > Sent: Wednesday, December 01, 2010 10:57 PM > > To: Hawrylewicz Czarnowski, Przemyslaw > > Cc: linux-raid@xxxxxxxxxxxxxxx; Labun, Marcin; Czarnowska, Anna; > Neubauer, > > Wojciech; Williams, Dan J; Ciechanowski, Ed > > Subject: Re: md as module cannot be reloaded. > > > > On Wed, 1 Dec 2010 14:23:14 +0000 "Hawrylewicz Czarnowski, Przemyslaw" > > <przemyslaw.hawrylewicz.czarnowski@xxxxxxxxx> wrote: > > > > > Hi, > > > > > > I have found an annoying problem with md module. If it is compiled as > > loadable module it is impossible to reload module if unloaded once. > > > > > > Eg. > > > # mdadm -Ss > > > # modprobe -r raid1 && modprobe -r md-mod > > > # cat /proc/modules | grep md_mod || echo Unloaded > > > Unloaded > > > # cat /proc/mdstat > > > cat /proc/mdstat: Invalid arguments > > > > I cannot reproduce this. That this point I get > > > > cat: /proc/mdstat: No such file or directory > > > > > > > # modprobe md-mod > > > # cat /proc/mdstat > > > cat /proc/mdstat: Invalid argument > > > # cat /proc/modules | grep md_mod || echo Unloaded > > > md_mod 94178 0 - Live 0xf857a000 > > > > > > Some functionalities seem to work, but nothing is able to read > > /proc/mdstat. > > > > > > If have tried few kernels from 2.6.27 to 2.6.37-rc3, openSUSE > 11.x/RHEL6, > > doesn't matter, still the same result. What can be wrong? > > > > openSUSE doesn't compile md as a module, it is compiled in to the kernel. > > But presumably you are compiling your own kernel with md as a module? Is > > that right? You aren't compiling a module and loading it into a kernel > > which > > already has md in it are you? I don't think that would work anyway... > Yes, I have recompiled kernel with MD as module. > > > > > And you give a full sequence of commands from loading to unload that > > reliably > > produces this error for you? > Ok, here you are: > * Original opensuse config updated to new kernel with defaults > * Changed CONFIG_BLK_DEV_MD=y->m > * Added prefix -mdadm > > make > su > make modules_install > make install > mdadm -Ss > mdadm --zero-superblock /dev/sd[b-g] > reboot > ... > localhost:~ # uname -r > 2.6.37-rc3-pae-mdadm > localhost:~ # cat /proc/mdstat > cat: /proc/mdstat: No such file or directory > localhost:~ # cat /proc/modules | grep md_mod > localhost:~ # modprobe md_mod > localhost:~ # ll /proc/mdstat > -r--r--r-- 1 root root 0 Dec 2 00:14 /proc/mdstat > localhost:~ # cat /proc/mdstat > Personalities : > unused devices: <none> > localhost:~ # modprobe -r md_mod > localhost:~ # ll /proc/mdstat > -r--r--r-- 1 root root 0 Dec 2 00:14 /proc/mdstat > localhost:~ # cat /proc/mdstat > cat: /proc/mdstat: Invalid argument > localhost:~ # modprobe -r md_mod Here is just "modprobe md_mod" of course... > localhost:~ # ll /proc/mdstat > -r--r--r-- 1 root root 0 Dec 2 00:14 /proc/mdstat > localhost:~ # cat /proc/mdstat > cat: /proc/mdstat: Invalid argument > > that's all. And another scenario - it might put some new light at this problem: [system right after restart] localhost:~ # mdadm -Ss mdadm: stopped /dev/md126 mdadm: stopped /dev/md127 localhost:~ # cat /proc/mdstat Personalities : [raid1] unused devices: <none> localhost:~ # modprobe -r raid1 localhost:~ # ll /proc/mdstat -r--r--r-- 1 root root 0 Dec 9 16:52 /proc/mdstat localhost:~ # cat /proc/mdstat cat: /proc/mdstat: Invalid argument One more thing... For some time everything worked perfectly. And problem appeared again after few days. I do not remember any unusual activity which may change this behavior. > > > > > NeilBrown > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
