On Tue, Mar 23, 2021 at 11:04:03AM -0600, Richard Henderson wrote: > On 3/22/21 5:54 PM, David Gibson wrote: > > On Mon, Mar 22, 2021 at 10:55:46AM -0600, Richard Henderson wrote: > > > On 3/21/21 9:52 PM, David Gibson wrote: > > > > > +/* > > > > > + * Bits for env->hflags. > > > > > + * > > > > > + * Most of these bits overlap with corresponding bits in MSR, > > > > > + * but some come from other sources. Be cautious when modifying. > > > > > > > > Yeah.. I'm not sure "be cautious" is enough of a warning. The exact > > > > value of some but not all of these flags must equal that for the > > > > corresponding MSR bits, which is terrifyingly subtle. > > > > > > Fair. How about, for the comment here, "This is validated in > > > hreg_compute_hflags." > > > > > > > > + /* Some bits come straight across from MSR. */ > > > > > + msr_mask = ((1 << MSR_LE) | (1 << MSR_PR) | > > > > > + (1 << MSR_DR) | (1 << MSR_IR) | > > > > > + (1 << MSR_FP) | (1 << MSR_SA) | (1 << MSR_AP)); > > > > > > Here, and in every other spot within this function where we manipulate > > > msr_mask, > > > > > > QEMU_BUILD_BUG_ON(MSR_LE != HFLAGS_LE); > > > > Seems reasonable. > > Hah. Your paranoia was well-founded. Typo in HFLAGS_PR. :-)
Heh :).
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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