Srivatsa S. Bhat
2022-May-20 15:41 UTC
[PATCH v2] x86/vmware: use unsigned integer for shifting
On 5/20/22 7:09 AM, Shreenidhi Shedi wrote:> From: Shreenidhi Shedi <yesshedi at gmail.com> > > From: Shreenidhi Shedi <sshedi at vmware.com> > > Shifting signed 32-bit value by 31 bits is implementation-defined > behaviour. Using unsigned is better option for this. > > Fixes: 4cca6ea04d31 ("x86/apic: Allow x2apic without IR on VMware platform") > > Signed-off-by: Shreenidhi Shedi <sshedi at vmware.com> > --- > arch/x86/kernel/cpu/vmware.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/kernel/cpu/vmware.c b/arch/x86/kernel/cpu/vmware.c > index c04b933f48d3..cd809c5b17f0 100644 > --- a/arch/x86/kernel/cpu/vmware.c > +++ b/arch/x86/kernel/cpu/vmware.c > @@ -28,6 +28,7 @@ > #include <linux/cpu.h> > #include <linux/reboot.h> > #include <linux/static_call.h> > +#include <linux/bits.h> > #include <asm/div64.h> > #include <asm/x86_init.h> > #include <asm/hypervisor.h> > @@ -476,8 +477,8 @@ 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))This patch has clearly not been tested, and not even compiled! (It is missing a semicolon at the end of the return statement). Please take your time to revise and test your patch based on the review feedback; there is no hurry! :) (Also, while at it, the double From: at the beginning of the patch needs to be fixed too). Regards, Srivatsa