Commit d08b4858 authored by Carlos Bilbao's avatar Carlos Bilbao Committed by Paolo Bonzini
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KVM: SVM: Name and check reserved fields with structs offset 

Rename reserved fields on all structs in arch/x86/include/asm/svm.h
following their offset within the structs. Include compile time checks for
this in the same place where other BUILD_BUG_ON for the structs are.

This also solves that fields of struct sev_es_save_area are named by their
order of appearance, but right now they jump from reserved_5 to reserved_7.

Link: https://lkml.org/lkml/2022/10/22/376


Signed-off-by: default avatarCarlos Bilbao <carlos.bilbao@amd.com>
Message-Id: <20221024164448.203351-1-carlos.bilbao@amd.com>
[Use ASSERT_STRUCT_OFFSET + fix a couple wrong offsets. - Paolo]
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 07a368b3

arch/x86/include/asm/svm.h

+65 −28
Original line number Diff line number Diff line
@@ -293,12 +293,13 @@ struct vmcb_save_area { 
	struct vmcb_seg ldtr;

	struct vmcb_seg idtr;

	struct vmcb_seg tr;

	u8 reserved_1[42];

	/* Reserved fields are named following their struct offset */

	u8 reserved_0xa0[42];

	u8 vmpl;

	u8 cpl;

	u8 reserved_2[4];

	u8 reserved_0xcc[4];

	u64 efer;

	u8 reserved_3[112];

	u8 reserved_0xd8[112];

	u64 cr4;

	u64 cr3;

	u64 cr0;
@@ -306,7 +307,7 @@ struct vmcb_save_area { 
	u64 dr6;

	u64 rflags;

	u64 rip;

	u8 reserved_4[88];

	u8 reserved_0x180[88];

	u64 rsp;

	u64 s_cet;

	u64 ssp;
@@ -321,14 +322,14 @@ struct vmcb_save_area { 
	u64 sysenter_esp;

	u64 sysenter_eip;

	u64 cr2;

	u8 reserved_5[32];

	u8 reserved_0x248[32];

	u64 g_pat;

	u64 dbgctl;

	u64 br_from;

	u64 br_to;

	u64 last_excp_from;

	u64 last_excp_to;

	u8 reserved_6[72];

	u8 reserved_0x298[72];

	u32 spec_ctrl;		/* Guest version of SPEC_CTRL at 0x2E0 */

} __packed;
@@ -349,12 +350,12 @@ struct sev_es_save_area { 
	u64 vmpl2_ssp;

	u64 vmpl3_ssp;

	u64 u_cet;

	u8 reserved_1[2];

	u8 reserved_0xc8[2];

	u8 vmpl;

	u8 cpl;

	u8 reserved_2[4];

	u8 reserved_0xcc[4];

	u64 efer;

	u8 reserved_3[104];

	u8 reserved_0xd8[104];

	u64 xss;

	u64 cr4;

	u64 cr3;
@@ -371,7 +372,7 @@ struct sev_es_save_area { 
	u64 dr1_addr_mask;

	u64 dr2_addr_mask;

	u64 dr3_addr_mask;

	u8 reserved_4[24];

	u8 reserved_0x1c0[24];

	u64 rsp;

	u64 s_cet;

	u64 ssp;
@@ -386,21 +387,21 @@ struct sev_es_save_area { 
	u64 sysenter_esp;

	u64 sysenter_eip;

	u64 cr2;

	u8 reserved_5[32];

	u8 reserved_0x248[32];

	u64 g_pat;

	u64 dbgctl;

	u64 br_from;

	u64 br_to;

	u64 last_excp_from;

	u64 last_excp_to;

	u8 reserved_7[80];

	u8 reserved_0x298[80];

	u32 pkru;

	u8 reserved_8[20];

	u64 reserved_9;		/* rax already available at 0x01f8 */

	u32 tsc_aux;

	u8 reserved_0x2f0[24];

	u64 rcx;

	u64 rdx;

	u64 rbx;

	u64 reserved_10;	/* rsp already available at 0x01d8 */

	u64 reserved_0x320;	/* rsp already available at 0x01d8 */

	u64 rbp;

	u64 rsi;

	u64 rdi;
@@ -412,7 +413,7 @@ struct sev_es_save_area { 
	u64 r13;

	u64 r14;

	u64 r15;

	u8 reserved_11[16];

	u8 reserved_0x380[16];

	u64 guest_exit_info_1;

	u64 guest_exit_info_2;

	u64 guest_exit_int_info;
@@ -425,7 +426,7 @@ struct sev_es_save_area { 
	u64 pcpu_id;

	u64 event_inj;

	u64 xcr0;

	u8 reserved_12[16];

	u8 reserved_0x3f0[16];



	/* Floating point area */

	u64 x87_dp;
@@ -443,23 +444,23 @@ struct sev_es_save_area { 
} __packed;



struct ghcb_save_area {

	u8 reserved_1[203];

	u8 reserved_0x0[203];

	u8 cpl;

	u8 reserved_2[116];

	u8 reserved_0xcc[116];

	u64 xss;

	u8 reserved_3[24];

	u8 reserved_0x148[24];

	u64 dr7;

	u8 reserved_4[16];

	u8 reserved_0x168[16];

	u64 rip;

	u8 reserved_5[88];

	u8 reserved_0x180[88];

	u64 rsp;

	u8 reserved_6[24];

	u8 reserved_0x1e0[24];

	u64 rax;

	u8 reserved_7[264];

	u8 reserved_0x200[264];

	u64 rcx;

	u64 rdx;

	u64 rbx;

	u8 reserved_8[8];

	u8 reserved_0x320[8];

	u64 rbp;

	u64 rsi;

	u64 rdi;
@@ -471,12 +472,12 @@ struct ghcb_save_area { 
	u64 r13;

	u64 r14;

	u64 r15;

	u8 reserved_9[16];

	u8 reserved_0x380[16];

	u64 sw_exit_code;

	u64 sw_exit_info_1;

	u64 sw_exit_info_2;

	u64 sw_scratch;

	u8 reserved_10[56];

	u8 reserved_0x3b0[56];

	u64 xcr0;

	u8 valid_bitmap[16];

	u64 x87_state_gpa;
@@ -490,7 +491,7 @@ struct ghcb { 


	u8 shared_buffer[GHCB_SHARED_BUF_SIZE];



	u8 reserved_1[10];

	u8 reserved_0xff0[10];

	u16 protocol_version;	/* negotiated SEV-ES/GHCB protocol version */

	u32 ghcb_usage;

} __packed;
@@ -502,6 +503,9 @@ struct ghcb { 
#define EXPECTED_VMCB_CONTROL_AREA_SIZE		1024

#define EXPECTED_GHCB_SIZE			PAGE_SIZE



#define BUILD_BUG_RESERVED_OFFSET(x, y) \

	ASSERT_STRUCT_OFFSET(struct x, reserved ## _ ## y, y)



static inline void __unused_size_checks(void)

{

	BUILD_BUG_ON(sizeof(struct vmcb_save_area)	!= EXPECTED_VMCB_SAVE_AREA_SIZE);
@@ -509,6 +513,39 @@ static inline void __unused_size_checks(void) 
	BUILD_BUG_ON(sizeof(struct sev_es_save_area)	!= EXPECTED_SEV_ES_SAVE_AREA_SIZE);

	BUILD_BUG_ON(sizeof(struct vmcb_control_area)	!= EXPECTED_VMCB_CONTROL_AREA_SIZE);

	BUILD_BUG_ON(sizeof(struct ghcb)		!= EXPECTED_GHCB_SIZE);



	/* Check offsets of reserved fields */



	BUILD_BUG_RESERVED_OFFSET(vmcb_save_area, 0xa0);

	BUILD_BUG_RESERVED_OFFSET(vmcb_save_area, 0xcc);

	BUILD_BUG_RESERVED_OFFSET(vmcb_save_area, 0xd8);

	BUILD_BUG_RESERVED_OFFSET(vmcb_save_area, 0x180);

	BUILD_BUG_RESERVED_OFFSET(vmcb_save_area, 0x248);

	BUILD_BUG_RESERVED_OFFSET(vmcb_save_area, 0x298);



	BUILD_BUG_RESERVED_OFFSET(sev_es_save_area, 0xc8);

	BUILD_BUG_RESERVED_OFFSET(sev_es_save_area, 0xcc);

	BUILD_BUG_RESERVED_OFFSET(sev_es_save_area, 0xd8);

	BUILD_BUG_RESERVED_OFFSET(sev_es_save_area, 0x1c0);

	BUILD_BUG_RESERVED_OFFSET(sev_es_save_area, 0x248);

	BUILD_BUG_RESERVED_OFFSET(sev_es_save_area, 0x298);

	BUILD_BUG_RESERVED_OFFSET(sev_es_save_area, 0x2f0);

	BUILD_BUG_RESERVED_OFFSET(sev_es_save_area, 0x320);

	BUILD_BUG_RESERVED_OFFSET(sev_es_save_area, 0x380);

	BUILD_BUG_RESERVED_OFFSET(sev_es_save_area, 0x3f0);



	BUILD_BUG_RESERVED_OFFSET(ghcb_save_area, 0x0);

	BUILD_BUG_RESERVED_OFFSET(ghcb_save_area, 0xcc);

	BUILD_BUG_RESERVED_OFFSET(ghcb_save_area, 0x148);

	BUILD_BUG_RESERVED_OFFSET(ghcb_save_area, 0x168);

	BUILD_BUG_RESERVED_OFFSET(ghcb_save_area, 0x180);

	BUILD_BUG_RESERVED_OFFSET(ghcb_save_area, 0x1e0);

	BUILD_BUG_RESERVED_OFFSET(ghcb_save_area, 0x200);

	BUILD_BUG_RESERVED_OFFSET(ghcb_save_area, 0x320);

	BUILD_BUG_RESERVED_OFFSET(ghcb_save_area, 0x380);

	BUILD_BUG_RESERVED_OFFSET(ghcb_save_area, 0x3b0);



	BUILD_BUG_RESERVED_OFFSET(ghcb, 0xff0);

}



struct vmcb {

arch/x86/kvm/svm/sev.c

+1 −1
Original line number Diff line number Diff line
@@ -2648,7 +2648,7 @@ static int setup_vmgexit_scratch(struct vcpu_svm *svm, bool sync, u64 len) 
		ghcb_scratch_beg = control->ghcb_gpa +

				   offsetof(struct ghcb, shared_buffer);

		ghcb_scratch_end = control->ghcb_gpa +

				   offsetof(struct ghcb, reserved_1);

				   offsetof(struct ghcb, reserved_0xff0);



		/*

		 * If the scratch area begins within the GHCB, it must be