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There's no need to hold > >> the lock for these computations. > >> > >> Signed-off-by: Jan Beulich > > > > Acked-by: Roger Pau Monné > > Thanks. > > > I had the same thought about moving the conversion out of the locked > > region when reviewing the previous patch. > > > > As noted in the previous patch, we should move the conversion of the > > century field with the rest? > > As said there, no, I don't think so. > > >> --- > >> How come RTC_ALWAYS_BCD is compile-time constant 1? And then even with an > >> inverted comment? Looks like we've inherited this from Linux, and even in > >> Linus'es current tree it's still this same way. Yet all half-way recent > >> chipsets I'm aware of properly implement the DM bit in reg B. Might this > >> be another 32-bit leftover? > > > > *shrugs* I don't know. Seems like Linux is still doing it, so it's > > likely safer for us to continue doing it also? We had no reports of > > it being problematic, albeit one could argue it would be best to > > prevent such reports by doing the right thing. > > That's my point. If we did this as specified, we'd unbreak systems with the > DM bit set correctly, but we'd break (hypothetical) systems with it bogusly > set. Like with a few other fixes, perhaps we should correct it, but provide > a command line option to restore old behavior? Possibly, but I would do after 4.22 has branched, just in case. One thing I've noticed, is that Xen don't attempts to set RTC_DM_BINARY in REG_B, shouldn't it try to set the bit when probing for the CMOS? Since it assumes BCD mode it should at least try to set it? Thanks, Roger.