Re: [Xen-devel] [PATCH] x86/xsave: simplify xcomp_bv initialization

2015-12-18 Thread Jan Beulich
>>> On 18.12.15 at 11:53, wrote: > On Thu, Dec 17, 2015 at 09:58:38AM -0700, Jan Beulich wrote: >> This eliminates a number of pointless conditionals: Bits 0 and 1 of >> xcomp_bv don't matter anyway, and as long as none of bits 2..62 are >> set, setting bit 63 is pointless too. >> > We should set

Re: [Xen-devel] [PATCH] x86/xsave: simplify xcomp_bv initialization

2015-12-18 Thread Shuai Ruan
On Thu, Dec 17, 2015 at 09:58:38AM -0700, Jan Beulich wrote: > This eliminates a number of pointless conditionals: Bits 0 and 1 of > xcomp_bv don't matter anyway, and as long as none of bits 2..62 are > set, setting bit 63 is pointless too. > We should set bit 63 of the xcomp_bv when initializatio

Re: [Xen-devel] [PATCH] x86/xsave: simplify xcomp_bv initialization

2015-12-17 Thread Andrew Cooper
On 17/12/15 16:58, Jan Beulich wrote: > This eliminates a number of pointless conditionals: Bits 0 and 1 of > xcomp_bv don't matter anyway, and as long as none of bits 2..62 are > set, setting bit 63 is pointless too. xcomp_bv[63] is the indication of whether the area is compressed or not. It wil