On Tue, Sep 6, 2011 at 9:31 PM, NeilBrown <neilb@xxxxxxx> wrote: > On Tue, 6 Sep 2011 12:16:43 -0700 "Williams, Dan J" > <dan.j.williams@xxxxxxxxx> wrote: > >> On Mon, Sep 5, 2011 at 7:23 AM, Labun, Marcin <Marcin.Labun@xxxxxxxxx> wrote: >> > Subject: [PATCH] kill-subarray: fix, cannot kill-subarray with unsupported metadata >> > >> > container_content retrieves volume information from disks in the container. >> > For unsupported volumes the function was not returning mdinfo. When all volumes >> > were unsupported the function was returning NULL pointer to block actions on the volumes. >> >> Isn't this the purpose of ->ignore_hw_compat? >> >> So we could do something simpler like the following instead? >> >> diff --git a/Kill.c b/Kill.c >> index b841a5b..11b27a6 100644 >> --- a/Kill.c >> +++ b/Kill.c >> @@ -97,7 +97,9 @@ int Kill_subarray(char *dev, char *subarray, int quiet) >> >> memset(st, 0, sizeof(*st)); >> >> + st->ignore_hw_compat = 1; >> fd = open_subarray(dev, subarray, st, quiet); >> + st->ignore_hw_compat = 0; >> if (fd < 0) >> return 2; > > While that is a *much* nicer patch, I don't think it will actually address > the problem. > You would at least need container_content_imsm to ignore > imsm_check_attributes if ->ignore_hw_compat was set. > > However I think things are getting a bit messy here and need to be cleaned up. > > Marcin's patch has the advantage that it treats the existence of a bad block > log and incompatible attributes in much the same way. > However I don't like: > - the increase in number of magic flag bits > - the editing of the list of arrays returned by container_content > - the error messages being printed by super-intel.c > > I think I would like: > - container_content always returns info about all arrays, so Examine and > Kill can work properly > - it sets a single flags (MD_SB_INVALID??) to say that the array cannot be > assembled or manipulated, and maybe stored a message string in the 'info' > so that common code can print it when it choses to ignore an array > - common code checks and ignores MD_SB_INVALID arrays as needed rather than > having them be removed from the list. > > Reasonable?? Yes, it would be nice to have a unified interface for reporting "please, don't assemble this because: foo" while also giving as much other info about the configuration as possible. Where foo is: "configuration crosses hardware domain boundary" "platform/metadata is using feature X that mdadm does not support" "raid array cannot be assembled without potentially exposing corrupted data" Then --force can uniformly override those concerns, probably for "Create" operations as well, but --force already has other meanings there. The ->ignore_hw_compat approach had the small beneficial side effect of whitelisting approved usages of potentially invalid information, but it should be no big deal to ensure those all get covered. -- 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
