On Fri, Aug 23, 2019 at 10:13:13AM +0200, Thomas Hellström (VMware) wrote: > From: Thomas Hellstrom <[email protected]> > > Vmware has historically used an "inl" instruction for this, but recent > hardware versions support using VMCALL/VMMCALL instead, so use this method > if supported at platform detection time. We explicitly need to code
Pls use passive voice in your commit message: no "we" or "I", etc, and describe your changes in imperative mood. > separate macro versions since the alternatives self-patching has not > been performed at platform detection time. > > Also put tighter constraints on the assembly input parameters. > > Cc: Thomas Gleixner <[email protected]> > Cc: Ingo Molnar <[email protected]> > Cc: Borislav Petkov <[email protected]> > Cc: "H. Peter Anvin" <[email protected]> > Cc: <[email protected]> > Cc: <[email protected]> > Co-developed-by: Doug Covelli <[email protected]> > Signed-off-by: Doug Covelli <[email protected]> > Signed-off-by: Thomas Hellstrom <[email protected]> > Reviewed-by: Doug Covelli <[email protected]> > --- > arch/x86/kernel/cpu/vmware.c | 88 +++++++++++++++++++++++++++++------- > 1 file changed, 71 insertions(+), 17 deletions(-) > > diff --git a/arch/x86/kernel/cpu/vmware.c b/arch/x86/kernel/cpu/vmware.c > index 3c648476d4fb..fcb84b1e099e 100644 > --- a/arch/x86/kernel/cpu/vmware.c > +++ b/arch/x86/kernel/cpu/vmware.c > @@ -30,34 +30,70 @@ > #include <asm/hypervisor.h> > #include <asm/timer.h> > #include <asm/apic.h> > +#include <asm/svm.h> That include is for? > #undef pr_fmt > #define pr_fmt(fmt) "vmware: " fmt > > -#define CPUID_VMWARE_INFO_LEAF 0x40000000 > +#define CPUID_VMWARE_INFO_LEAF 0x40000000 > +#define CPUID_VMWARE_FEATURES_LEAF 0x40000010 > +#define CPUID_VMWARE_FEATURES_ECX_VMMCALL BIT(0) > +#define CPUID_VMWARE_FEATURES_ECX_VMCALL BIT(1) > + > #define VMWARE_HYPERVISOR_MAGIC 0x564D5868 > #define VMWARE_HYPERVISOR_PORT 0x5658 > > -#define VMWARE_PORT_CMD_GETVERSION 10 > -#define VMWARE_PORT_CMD_GETHZ 45 > -#define VMWARE_PORT_CMD_GETVCPU_INFO 68 > -#define VMWARE_PORT_CMD_LEGACY_X2APIC 3 > -#define VMWARE_PORT_CMD_VCPU_RESERVED 31 > +#define VMWARE_CMD_GETVERSION 10 > +#define VMWARE_CMD_GETHZ 45 > +#define VMWARE_CMD_GETVCPU_INFO 68 > +#define VMWARE_CMD_LEGACY_X2APIC 3 > +#define VMWARE_CMD_VCPU_RESERVED 31 > > #define VMWARE_PORT(cmd, eax, ebx, ecx, edx) \ > __asm__("inl (%%dx)" : \ > - "=a"(eax), "=c"(ecx), "=d"(edx), "=b"(ebx) : \ > - "0"(VMWARE_HYPERVISOR_MAGIC), \ > - "1"(VMWARE_PORT_CMD_##cmd), \ > - "2"(VMWARE_HYPERVISOR_PORT), "3"(UINT_MAX) : \ > - "memory"); > + "=a"(eax), "=c"(ecx), "=d"(edx), "=b"(ebx) : \ > + "a"(VMWARE_HYPERVISOR_MAGIC), \ > + "c"(VMWARE_CMD_##cmd), \ > + "d"(VMWARE_HYPERVISOR_PORT), "b"(UINT_MAX) : \ > + "memory") > + > +#define VMWARE_VMCALL(cmd, eax, ebx, ecx, edx) > \ > + __asm__("vmcall" : \ > + "=a"(eax), "=c"(ecx), "=d"(edx), "=b"(ebx) : \ > + "a"(VMWARE_HYPERVISOR_MAGIC), \ > + "c"(VMWARE_CMD_##cmd), \ > + "d"(0), "b"(UINT_MAX) : \ > + "memory") > + > +#define VMWARE_VMMCALL(cmd, eax, ebx, ecx, edx) \ > + __asm__("vmmcall" : \ > + "=a"(eax), "=c"(ecx), "=d"(edx), "=b"(ebx) : \ > + "a"(VMWARE_HYPERVISOR_MAGIC), \ > + "c"(VMWARE_CMD_##cmd), \ > + "d"(0), "b"(UINT_MAX) : \ > + "memory") > + > +#define VMWARE_CMD(cmd, eax, ebx, ecx, edx) do { \ > + switch (vmware_hypercall_mode) { \ > + case CPUID_VMWARE_FEATURES_ECX_VMCALL: \ > + VMWARE_VMCALL(cmd, eax, ebx, ecx, edx); \ > + break; \ > + case CPUID_VMWARE_FEATURES_ECX_VMMCALL: \ > + VMWARE_VMMCALL(cmd, eax, ebx, ecx, edx); \ > + break; \ > + default: \ Please integrate scripts/checkpatch.pl into your patch creation workflow. Some of the warnings/errors *actually* make sense: WARNING: Possible switch case/default not preceded by break or fallthrough comment #110: FILE: arch/x86/kernel/cpu/vmware.c:81: + case CPUID_VMWARE_FEATURES_ECX_VMMCALL: \ WARNING: Possible switch case/default not preceded by break or fallthrough comment #113: FILE: arch/x86/kernel/cpu/vmware.c:84: + default: In this case, we're going to enable -Wimplicit-fallthrough by default at some point. > + VMWARE_PORT(cmd, eax, ebx, ecx, edx); \ > + break; \ > + } \ > + } while (0) > > static unsigned long vmware_tsc_khz __ro_after_init; > +static u8 vmware_hypercall_mode __ro_after_init; > > static inline int __vmware_platform(void) > { > uint32_t eax, ebx, ecx, edx; > - VMWARE_PORT(GETVERSION, eax, ebx, ecx, edx); > + VMWARE_CMD(GETVERSION, eax, ebx, ecx, edx); > return eax != (uint32_t)-1 && ebx == VMWARE_HYPERVISOR_MAGIC; > } > > @@ -136,7 +172,7 @@ static void __init vmware_platform_setup(void) > uint32_t eax, ebx, ecx, edx; > uint64_t lpj, tsc_khz; > > - VMWARE_PORT(GETHZ, eax, ebx, ecx, edx); > + VMWARE_CMD(GETHZ, eax, ebx, ecx, edx); > > if (ebx != UINT_MAX) { > lpj = tsc_khz = eax | (((uint64_t)ebx) << 32); > @@ -174,6 +210,16 @@ static void __init vmware_platform_setup(void) > vmware_set_capabilities(); > } > > +static u8 No need for that linebreak here. > +vmware_select_hypercall(void) > +{ > + int eax, ebx, ecx, edx; > + > + cpuid(CPUID_VMWARE_FEATURES_LEAF, &eax, &ebx, &ecx, &edx); > + return (ecx & (CPUID_VMWARE_FEATURES_ECX_VMMCALL | > + CPUID_VMWARE_FEATURES_ECX_VMCALL)); > +} > + > /* > * While checking the dmi string information, just checking the product > * serial key should be enough, as this will always have a VMware > @@ -187,8 +233,16 @@ static uint32_t __init vmware_platform(void) > > cpuid(CPUID_VMWARE_INFO_LEAF, &eax, &hyper_vendor_id[0], > &hyper_vendor_id[1], &hyper_vendor_id[2]); > - if (!memcmp(hyper_vendor_id, "VMwareVMware", 12)) > + if (!memcmp(hyper_vendor_id, "VMwareVMware", 12)) { > + if (eax >= CPUID_VMWARE_FEATURES_LEAF) > + vmware_hypercall_mode = > + vmware_select_hypercall(); > + > + pr_info("hypercall mode: 0x%02x\n", > + (unsigned int) vmware_hypercall_mode); Is that supposed to be debug output? If so, pr_dbg(). > + > return CPUID_VMWARE_INFO_LEAF; > + } > } else if (dmi_available && dmi_name_in_serial("VMware") && > __vmware_platform()) What sets vmware_hypercall_mode in this case? Or is the 0 magic to mean, use the default: VMWARE_PORT inl call? Also, you could restructure that function something like this to save yourself an indentation level or two and make it more easily readable: static uint32_t __init vmware_platform(void) { unsigned int hyper_vendor_id[3]; unsigned int eax; if (!boot_cpu_has(X86_FEATURE_HYPERVISOR)) { if (dmi_available && dmi_name_in_serial("VMware") && __vmware_platform()) return 1; } cpuid(CPUID_VMWARE_INFO_LEAF, &eax, &hyper_vendor_id[0], &hyper_vendor_id[1], &hyper_vendor_id[2]); if (!memcmp(hyper_vendor_id, "VMwareVMware", 12)) { if (eax >= CPUID_VMWARE_FEATURES_LEAF) vmware_hypercall_mode = vmware_select_hypercall(); pr_info("hypercall mode: 0x%02x\n", (unsigned int) vmware_hypercall_mode); return CPUID_VMWARE_INFO_LEAF; } return 0; } -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.
