Messages in this thread | | | Date | Mon, 9 Nov 2020 18:09:40 +0100 | From | Greg Kroah-Hartman <> | Subject | Re: [PATCH v5 07/17] virt: acrn: Introduce an ioctl to set vCPU registers state |
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On Mon, Oct 19, 2020 at 02:17:53PM +0800, shuo.a.liu@intel.com wrote: > From: Shuo Liu <shuo.a.liu@intel.com> > > A virtual CPU of User VM has different context due to the different > registers state. ACRN userspace needs to set the virtual CPU > registers state (e.g. giving a initial registers state to a virtual > BSP of a User VM). > > HSM provides an ioctl ACRN_IOCTL_SET_VCPU_REGS to do the virtual CPU > registers state setting. The ioctl passes the registers state from ACRN > userspace to the hypervisor directly. > > Signed-off-by: Shuo Liu <shuo.a.liu@intel.com> > Reviewed-by: Zhi Wang <zhi.a.wang@intel.com> > Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> > Cc: Zhi Wang <zhi.a.wang@intel.com> > Cc: Zhenyu Wang <zhenyuw@linux.intel.com> > Cc: Yu Wang <yu1.wang@intel.com> > Cc: Reinette Chatre <reinette.chatre@intel.com> > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > --- > drivers/virt/acrn/hsm.c | 15 ++++++++ > drivers/virt/acrn/hypercall.h | 13 +++++++ > include/uapi/linux/acrn.h | 71 +++++++++++++++++++++++++++++++++++ > 3 files changed, 99 insertions(+) > > diff --git a/drivers/virt/acrn/hsm.c b/drivers/virt/acrn/hsm.c > index cbda67d4eb89..58ceb02e82db 100644 > --- a/drivers/virt/acrn/hsm.c > +++ b/drivers/virt/acrn/hsm.c > @@ -9,6 +9,7 @@ > * Yakui Zhao <yakui.zhao@intel.com> > */ > > +#include <linux/io.h> > #include <linux/mm.h> > #include <linux/module.h> > #include <linux/slab.h> > @@ -46,6 +47,7 @@ static long acrn_dev_ioctl(struct file *filp, unsigned int cmd, > { > struct acrn_vm *vm = filp->private_data; > struct acrn_vm_creation *vm_param; > + struct acrn_vcpu_regs *cpu_regs; > int ret = 0; > > if (vm->vmid == ACRN_INVALID_VMID && cmd != ACRN_IOCTL_CREATE_VM) { > @@ -97,6 +99,19 @@ static long acrn_dev_ioctl(struct file *filp, unsigned int cmd, > case ACRN_IOCTL_DESTROY_VM: > ret = acrn_vm_destroy(vm); > break; > + case ACRN_IOCTL_SET_VCPU_REGS: > + cpu_regs = memdup_user((void __user *)ioctl_param, > + sizeof(struct acrn_vcpu_regs)); > + if (IS_ERR(cpu_regs)) > + return PTR_ERR(cpu_regs); > + > + ret = hcall_set_vcpu_regs(vm->vmid, virt_to_phys(cpu_regs));
Why the virt_to_phys() call here? And there really is no validation of any fields?
> + if (ret < 0) > + dev_dbg(acrn_dev.this_device,
Wait, a global, static device? Where did I miss that? That feels odd, why is there just one?
> + "Failed to set regs state of VM%u!\n", > + vm->vmid); > + kfree(cpu_regs); > + break; > default: > dev_dbg(acrn_dev.this_device, "Unknown IOCTL 0x%x!\n", cmd); > ret = -ENOTTY; > diff --git a/drivers/virt/acrn/hypercall.h b/drivers/virt/acrn/hypercall.h > index 426b66cadb1f..f29cfae08862 100644 > --- a/drivers/virt/acrn/hypercall.h > +++ b/drivers/virt/acrn/hypercall.h > @@ -19,6 +19,7 @@ > #define HC_START_VM _HC_ID(HC_ID, HC_ID_VM_BASE + 0x02) > #define HC_PAUSE_VM _HC_ID(HC_ID, HC_ID_VM_BASE + 0x03) > #define HC_RESET_VM _HC_ID(HC_ID, HC_ID_VM_BASE + 0x05) > +#define HC_SET_VCPU_REGS _HC_ID(HC_ID, HC_ID_VM_BASE + 0x06) > > /** > * hcall_create_vm() - Create a User VM > @@ -75,4 +76,16 @@ static inline long hcall_reset_vm(u64 vmid) > return acrn_hypercall1(HC_RESET_VM, vmid); > } > > +/** > + * hcall_set_vcpu_regs() - Set up registers of virtual CPU of a User VM > + * @vmid: User VM ID > + * @regs_state: Service VM GPA of registers state > + * > + * Return: 0 on success, <0 on failure > + */ > +static inline long hcall_set_vcpu_regs(u64 vmid, u64 regs_state) > +{ > + return acrn_hypercall2(HC_SET_VCPU_REGS, vmid, regs_state); > +} > + > #endif /* __ACRN_HSM_HYPERCALL_H */ > diff --git a/include/uapi/linux/acrn.h b/include/uapi/linux/acrn.h > index 364b1a783074..1d5b82e154fb 100644 > --- a/include/uapi/linux/acrn.h > +++ b/include/uapi/linux/acrn.h > @@ -36,6 +36,75 @@ struct acrn_vm_creation { > __u8 reserved2[8]; > } __attribute__((aligned(8))); > > +struct acrn_gp_regs { > + __u64 rax; > + __u64 rcx; > + __u64 rdx; > + __u64 rbx; > + __u64 rsp; > + __u64 rbp; > + __u64 rsi; > + __u64 rdi; > + __u64 r8; > + __u64 r9; > + __u64 r10; > + __u64 r11; > + __u64 r12; > + __u64 r13; > + __u64 r14; > + __u64 r15; > +}; > + > +struct acrn_descriptor_ptr { > + __u16 limit; > + __u64 base; > + __u16 reserved[3]; > +} __attribute__ ((__packed__)); > + > +struct acrn_regs { > + struct acrn_gp_regs gprs; > + struct acrn_descriptor_ptr gdt; > + struct acrn_descriptor_ptr idt; > + > + __u64 rip;
As these are all crossing the user/kernel boundry and then on to somewhere "else", you have to specify the endian of all of these, right?
if not, why not?
> + __u64 cs_base; > + __u64 cr0; > + __u64 cr4; > + __u64 cr3; > + __u64 ia32_efer; > + __u64 rflags; > + __u64 reserved_64[4]; > + > + __u32 cs_ar; > + __u32 cs_limit; > + __u32 reserved_32[3]; > + > + __u16 cs_sel; > + __u16 ss_sel; > + __u16 ds_sel; > + __u16 es_sel; > + __u16 fs_sel; > + __u16 gs_sel; > + __u16 ldt_sel; > + __u16 tr_sel; > + > + __u16 reserved_16[4]; > +}; > + > +/** > + * struct acrn_vcpu_regs - Info of vCPU registers state > + * @vcpu_id: vCPU ID > + * @reserved0: Reserved > + * @vcpu_regs: vCPU registers state > + * > + * This structure will be passed to hypervisor directly. > + */ > +struct acrn_vcpu_regs { > + __u16 vcpu_id;
Endian?
> + __u16 reserved0[3];
What does the reserved fields do?
Is there a pointer to a public document for all of these structures somewhere?
> + struct acrn_regs vcpu_regs; > +} __attribute__((aligned(8)));
What does the alignment do here?
thanks,
greg k-h
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