On 12/8/21 01:03, Yang Zhong wrote:
+ +#ifdef CONFIG_X86_64 + if ((xcr0 & XFEATURE_MASK_XTILE) && + ((xcr0 & XFEATURE_MASK_XTILE) != XFEATURE_MASK_XTILE)) + return 1; +#else + /* + * Intel AMX instructions can be executed only in 64-bit mode but + * XSAVE can operate on XTILECFG and XTILEDATA in any mode. + * Since the FPU core follows SDM recommendation to set + * XCR[18:17] only in 64-bit environment, here also prevent any + * guest OS from setting the two bits when host is 32-bit. + * + * XFEATURE_MASK_XTILE cannot be used since it is 0 in this case. + */ + xcr0 &= ~(XFEATURE_MASK_XTILE_DATA | XFEATURE_MASK_XTILE_CFG); +#endif
This should not be necessary, because on a 32-bit system the bits won't be part of supported_xcr0.
Paolo
