Commit 4745ca43 authored by Shreenidhi Shedi's avatar Shreenidhi Shedi Committed by Borislav Petkov
Browse files

x86/vmware: Use BIT() macro for shifting 



VMWARE_CMD_VCPU_RESERVED is bit 31 and that would mean undefined
behavior when shifting an int but the kernel is built with
-fno-strict-overflow which will wrap around using two's complement.

Use the BIT() macro to improve readability and avoid any potential
overflow confusion because it uses an unsigned long.

  [ bp: Clarify commit message. ]

Signed-off-by: default avatarShreenidhi Shedi <sshedi@vmware.com>
Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
Reviewed-by: default avatarSrivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Link: https://lore.kernel.org/r/20220601101820.535031-1-sshedi@vmware.com
parent a111daf0

arch/x86/kernel/cpu/vmware.c

+2 −2
Original line number Diff line number Diff line
@@ -476,8 +476,8 @@ static bool __init vmware_legacy_x2apic_available(void) 
{

	uint32_t eax, ebx, ecx, edx;

	VMWARE_CMD(GETVCPU_INFO, eax, ebx, ecx, edx);

	return (eax & (1 << VMWARE_CMD_VCPU_RESERVED)) == 0 &&

	       (eax & (1 << VMWARE_CMD_LEGACY_X2APIC)) != 0;

	return !(eax & BIT(VMWARE_CMD_VCPU_RESERVED)) &&

		(eax & BIT(VMWARE_CMD_LEGACY_X2APIC));

}



#ifdef CONFIG_AMD_MEM_ENCRYPT