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Juergen Gross

2020-Aug-15 10:06 UTC

[PATCH v4 0/6] x86/paravirt: cleanup after 32-bit PV removal

A lot of cleanup after removal of 32-bit Xen PV guest support in
paravirt code.

Changes in V4:
- dropped patches 1-3, as already committed
- addressed comments to V3
- added new patches 5+6

Changes in V3:
- addressed comments to V2
- split patch 1 into 2 patches
- new patches 3 and 7

Changes in V2:
- rebase to 5.8 kernel
- addressed comments to V1
- new patches 3 and 4

Juergen Gross (6):
  x86/paravirt: remove 32-bit support from PARAVIRT_XXL
  x86/paravirt: cleanup paravirt macros
  x86/paravirt: use CONFIG_PARAVIRT_XXL instead of CONFIG_PARAVIRT
  x86/entry/32: revert "Fix XEN_PV build dependency"
  x86/paravirt: remove set_pte_at pv-op
  x86/paravirt: avoid needless paravirt step clearing page table entries

 arch/x86/entry/entry_64.S                   |   4 +-
 arch/x86/entry/vdso/vdso32/vclock_gettime.c |   1 +
 arch/x86/include/asm/fixmap.h               |   2 +-
 arch/x86/include/asm/idtentry.h             |   4 +-
 arch/x86/include/asm/paravirt.h             | 151 +++-----------------
 arch/x86/include/asm/paravirt_types.h       |  23 ---
 arch/x86/include/asm/pgtable-3level_types.h |   5 -
 arch/x86/include/asm/pgtable.h              |   7 +-
 arch/x86/include/asm/required-features.h    |   2 +-
 arch/x86/include/asm/segment.h              |   4 -
 arch/x86/kernel/cpu/common.c                |   8 --
 arch/x86/kernel/kprobes/core.c              |   1 -
 arch/x86/kernel/kprobes/opt.c               |   1 -
 arch/x86/kernel/paravirt.c                  |  19 ---
 arch/x86/kernel/paravirt_patch.c            |  17 ---
 arch/x86/xen/enlighten_pv.c                 |   6 -
 arch/x86/xen/mmu_pv.c                       |   8 --
 include/trace/events/xen.h                  |  20 ---
 18 files changed, 27 insertions(+), 256 deletions(-)

-- 
2.26.2

Juergen Gross

2020-Aug-15 10:06 UTC

head link

[PATCH v4 1/6] x86/paravirt: remove 32-bit support from PARAVIRT_XXL

The last 32-bit user of stuff under CONFIG_PARAVIRT_XXL is gone.

Remove 32-bit specific parts.

Signed-off-by: Juergen Gross <jgross at suse.com>
---
 arch/x86/entry/vdso/vdso32/vclock_gettime.c |   1 +
 arch/x86/include/asm/paravirt.h             | 120 ++------------------
 arch/x86/include/asm/paravirt_types.h       |  21 ----
 arch/x86/include/asm/pgtable-3level_types.h |   5 -
 arch/x86/include/asm/segment.h              |   4 -
 arch/x86/kernel/cpu/common.c                |   8 --
 arch/x86/kernel/kprobes/core.c              |   1 -
 arch/x86/kernel/kprobes/opt.c               |   1 -
 arch/x86/kernel/paravirt.c                  |  18 ---
 arch/x86/kernel/paravirt_patch.c            |  17 ---
 arch/x86/xen/enlighten_pv.c                 |   6 -
 11 files changed, 13 insertions(+), 189 deletions(-)

diff --git a/arch/x86/entry/vdso/vdso32/vclock_gettime.c
b/arch/x86/entry/vdso/vdso32/vclock_gettime.c
index 84a4a73f77f7..283ed9d00426 100644
--- a/arch/x86/entry/vdso/vdso32/vclock_gettime.c
+++ b/arch/x86/entry/vdso/vdso32/vclock_gettime.c
@@ -14,6 +14,7 @@
 #undef CONFIG_ILLEGAL_POINTER_VALUE
 #undef CONFIG_SPARSEMEM_VMEMMAP
 #undef CONFIG_NR_CPUS
+#undef CONFIG_PARAVIRT_XXL
 
 #define CONFIG_X86_32 1
 #define CONFIG_PGTABLE_LEVELS 2
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index 3d2afecde50c..25c7a73461f6 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -160,8 +160,6 @@ static inline void wbinvd(void)
 	PVOP_VCALL0(cpu.wbinvd);
 }
 
-#define get_kernel_rpl()  (pv_info.kernel_rpl)
-
 static inline u64 paravirt_read_msr(unsigned msr)
 {
 	return PVOP_CALL1(u64, cpu.read_msr, msr);
@@ -277,12 +275,10 @@ static inline void load_TLS(struct thread_struct *t,
unsigned cpu)
 	PVOP_VCALL2(cpu.load_tls, t, cpu);
 }
 
-#ifdef CONFIG_X86_64
 static inline void load_gs_index(unsigned int gs)
 {
 	PVOP_VCALL1(cpu.load_gs_index, gs);
 }
-#endif
 
 static inline void write_ldt_entry(struct desc_struct *dt, int entry,
 				   const void *desc)
@@ -375,52 +371,22 @@ static inline void paravirt_release_p4d(unsigned long pfn)
 
 static inline pte_t __pte(pteval_t val)
 {
-	pteval_t ret;
-
-	if (sizeof(pteval_t) > sizeof(long))
-		ret = PVOP_CALLEE2(pteval_t, mmu.make_pte, val, (u64)val >> 32);
-	else
-		ret = PVOP_CALLEE1(pteval_t, mmu.make_pte, val);
-
-	return (pte_t) { .pte = ret };
+	return (pte_t) { PVOP_CALLEE1(pteval_t, mmu.make_pte, val) };
 }
 
 static inline pteval_t pte_val(pte_t pte)
 {
-	pteval_t ret;
-
-	if (sizeof(pteval_t) > sizeof(long))
-		ret = PVOP_CALLEE2(pteval_t, mmu.pte_val,
-				   pte.pte, (u64)pte.pte >> 32);
-	else
-		ret = PVOP_CALLEE1(pteval_t, mmu.pte_val, pte.pte);
-
-	return ret;
+	return PVOP_CALLEE1(pteval_t, mmu.pte_val, pte.pte);
 }
 
 static inline pgd_t __pgd(pgdval_t val)
 {
-	pgdval_t ret;
-
-	if (sizeof(pgdval_t) > sizeof(long))
-		ret = PVOP_CALLEE2(pgdval_t, mmu.make_pgd, val, (u64)val >> 32);
-	else
-		ret = PVOP_CALLEE1(pgdval_t, mmu.make_pgd, val);
-
-	return (pgd_t) { ret };
+	return (pgd_t) { PVOP_CALLEE1(pgdval_t, mmu.make_pgd, val) };
 }
 
 static inline pgdval_t pgd_val(pgd_t pgd)
 {
-	pgdval_t ret;
-
-	if (sizeof(pgdval_t) > sizeof(long))
-		ret =  PVOP_CALLEE2(pgdval_t, mmu.pgd_val,
-				    pgd.pgd, (u64)pgd.pgd >> 32);
-	else
-		ret =  PVOP_CALLEE1(pgdval_t, mmu.pgd_val, pgd.pgd);
-
-	return ret;
+	return PVOP_CALLEE1(pgdval_t, mmu.pgd_val, pgd.pgd);
 }
 
 #define  __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION
@@ -438,78 +404,40 @@ static inline void ptep_modify_prot_commit(struct
vm_area_struct *vma, unsigned
 					   pte_t *ptep, pte_t old_pte, pte_t pte)
 {
 
-	if (sizeof(pteval_t) > sizeof(long))
-		/* 5 arg words */
-		pv_ops.mmu.ptep_modify_prot_commit(vma, addr, ptep, pte);
-	else
-		PVOP_VCALL4(mmu.ptep_modify_prot_commit,
-			    vma, addr, ptep, pte.pte);
+	PVOP_VCALL4(mmu.ptep_modify_prot_commit, vma, addr, ptep, pte.pte);
 }
 
 static inline void set_pte(pte_t *ptep, pte_t pte)
 {
-	if (sizeof(pteval_t) > sizeof(long))
-		PVOP_VCALL3(mmu.set_pte, ptep, pte.pte, (u64)pte.pte >> 32);
-	else
-		PVOP_VCALL2(mmu.set_pte, ptep, pte.pte);
+	PVOP_VCALL2(mmu.set_pte, ptep, pte.pte);
 }
 
 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
 			      pte_t *ptep, pte_t pte)
 {
-	if (sizeof(pteval_t) > sizeof(long))
-		/* 5 arg words */
-		pv_ops.mmu.set_pte_at(mm, addr, ptep, pte);
-	else
-		PVOP_VCALL4(mmu.set_pte_at, mm, addr, ptep, pte.pte);
+	PVOP_VCALL4(mmu.set_pte_at, mm, addr, ptep, pte.pte);
 }
 
 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
 {
-	pmdval_t val = native_pmd_val(pmd);
-
-	if (sizeof(pmdval_t) > sizeof(long))
-		PVOP_VCALL3(mmu.set_pmd, pmdp, val, (u64)val >> 32);
-	else
-		PVOP_VCALL2(mmu.set_pmd, pmdp, val);
+	PVOP_VCALL2(mmu.set_pmd, pmdp, native_pmd_val(pmd));
 }
 
-#if CONFIG_PGTABLE_LEVELS >= 3
 static inline pmd_t __pmd(pmdval_t val)
 {
-	pmdval_t ret;
-
-	if (sizeof(pmdval_t) > sizeof(long))
-		ret = PVOP_CALLEE2(pmdval_t, mmu.make_pmd, val, (u64)val >> 32);
-	else
-		ret = PVOP_CALLEE1(pmdval_t, mmu.make_pmd, val);
-
-	return (pmd_t) { ret };
+	return (pmd_t) { PVOP_CALLEE1(pmdval_t, mmu.make_pmd, val) };
 }
 
 static inline pmdval_t pmd_val(pmd_t pmd)
 {
-	pmdval_t ret;
-
-	if (sizeof(pmdval_t) > sizeof(long))
-		ret =  PVOP_CALLEE2(pmdval_t, mmu.pmd_val,
-				    pmd.pmd, (u64)pmd.pmd >> 32);
-	else
-		ret =  PVOP_CALLEE1(pmdval_t, mmu.pmd_val, pmd.pmd);
-
-	return ret;
+	return PVOP_CALLEE1(pmdval_t, mmu.pmd_val, pmd.pmd);
 }
 
 static inline void set_pud(pud_t *pudp, pud_t pud)
 {
-	pudval_t val = native_pud_val(pud);
-
-	if (sizeof(pudval_t) > sizeof(long))
-		PVOP_VCALL3(mmu.set_pud, pudp, val, (u64)val >> 32);
-	else
-		PVOP_VCALL2(mmu.set_pud, pudp, val);
+	PVOP_VCALL2(mmu.set_pud, pudp, native_pud_val(pud));
 }
-#if CONFIG_PGTABLE_LEVELS >= 4
+
 static inline pud_t __pud(pudval_t val)
 {
 	pudval_t ret;
@@ -574,29 +502,6 @@ static inline void p4d_clear(p4d_t *p4dp)
 	set_p4d(p4dp, __p4d(0));
 }
 
-#endif	/* CONFIG_PGTABLE_LEVELS == 4 */
-
-#endif	/* CONFIG_PGTABLE_LEVELS >= 3 */
-
-#ifdef CONFIG_X86_PAE
-/* Special-case pte-setting operations for PAE, which can't update a
-   64-bit pte atomically */
-static inline void set_pte_atomic(pte_t *ptep, pte_t pte)
-{
-	PVOP_VCALL3(mmu.set_pte_atomic, ptep, pte.pte, pte.pte >> 32);
-}
-
-static inline void pte_clear(struct mm_struct *mm, unsigned long addr,
-			     pte_t *ptep)
-{
-	PVOP_VCALL3(mmu.pte_clear, mm, addr, ptep);
-}
-
-static inline void pmd_clear(pmd_t *pmdp)
-{
-	PVOP_VCALL1(mmu.pmd_clear, pmdp);
-}
-#else  /* !CONFIG_X86_PAE */
 static inline void set_pte_atomic(pte_t *ptep, pte_t pte)
 {
 	set_pte(ptep, pte);
@@ -612,7 +517,6 @@ static inline void pmd_clear(pmd_t *pmdp)
 {
 	set_pmd(pmdp, __pmd(0));
 }
-#endif	/* CONFIG_X86_PAE */
 
 #define  __HAVE_ARCH_START_CONTEXT_SWITCH
 static inline void arch_start_context_switch(struct task_struct *prev)
diff --git a/arch/x86/include/asm/paravirt_types.h
b/arch/x86/include/asm/paravirt_types.h
index 8dfcb2508e6d..f27c3febaa6e 100644
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -68,12 +68,7 @@ struct paravirt_callee_save {
 /* general info */
 struct pv_info {
 #ifdef CONFIG_PARAVIRT_XXL
-	unsigned int kernel_rpl;
-	int shared_kernel_pmd;
-
-#ifdef CONFIG_X86_64
 	u16 extra_user_64bit_cs;  /* __USER_CS if none */
-#endif
 #endif
 
 	const char *name;
@@ -126,9 +121,7 @@ struct pv_cpu_ops {
 	void (*set_ldt)(const void *desc, unsigned entries);
 	unsigned long (*store_tr)(void);
 	void (*load_tls)(struct thread_struct *t, unsigned int cpu);
-#ifdef CONFIG_X86_64
 	void (*load_gs_index)(unsigned int idx);
-#endif
 	void (*write_ldt_entry)(struct desc_struct *ldt, int entrynum,
 				const void *desc);
 	void (*write_gdt_entry)(struct desc_struct *,
@@ -264,21 +257,11 @@ struct pv_mmu_ops {
 	struct paravirt_callee_save pgd_val;
 	struct paravirt_callee_save make_pgd;
 
-#if CONFIG_PGTABLE_LEVELS >= 3
-#ifdef CONFIG_X86_PAE
-	void (*set_pte_atomic)(pte_t *ptep, pte_t pteval);
-	void (*pte_clear)(struct mm_struct *mm, unsigned long addr,
-			  pte_t *ptep);
-	void (*pmd_clear)(pmd_t *pmdp);
-
-#endif	/* CONFIG_X86_PAE */
-
 	void (*set_pud)(pud_t *pudp, pud_t pudval);
 
 	struct paravirt_callee_save pmd_val;
 	struct paravirt_callee_save make_pmd;
 
-#if CONFIG_PGTABLE_LEVELS >= 4
 	struct paravirt_callee_save pud_val;
 	struct paravirt_callee_save make_pud;
 
@@ -291,10 +274,6 @@ struct pv_mmu_ops {
 	void (*set_pgd)(pgd_t *pgdp, pgd_t pgdval);
 #endif	/* CONFIG_PGTABLE_LEVELS >= 5 */
 
-#endif	/* CONFIG_PGTABLE_LEVELS >= 4 */
-
-#endif	/* CONFIG_PGTABLE_LEVELS >= 3 */
-
 	struct pv_lazy_ops lazy_mode;
 
 	/* dom0 ops */
diff --git a/arch/x86/include/asm/pgtable-3level_types.h
b/arch/x86/include/asm/pgtable-3level_types.h
index 80fbb4a9ed87..56baf43befb4 100644
--- a/arch/x86/include/asm/pgtable-3level_types.h
+++ b/arch/x86/include/asm/pgtable-3level_types.h
@@ -20,12 +20,7 @@ typedef union {
 } pte_t;
 #endif	/* !__ASSEMBLY__ */
 
-#ifdef CONFIG_PARAVIRT_XXL
-#define SHARED_KERNEL_PMD	((!static_cpu_has(X86_FEATURE_PTI) &&	\
-				 (pv_info.shared_kernel_pmd)))
-#else
 #define SHARED_KERNEL_PMD	(!static_cpu_has(X86_FEATURE_PTI))
-#endif
 
 #define ARCH_PAGE_TABLE_SYNC_MASK	(SHARED_KERNEL_PMD ? 0 : PGTBL_PMD_MODIFIED)
 
diff --git a/arch/x86/include/asm/segment.h b/arch/x86/include/asm/segment.h
index 9646c300f128..517920928989 100644
--- a/arch/x86/include/asm/segment.h
+++ b/arch/x86/include/asm/segment.h
@@ -222,10 +222,6 @@
 
 #endif
 
-#ifndef CONFIG_PARAVIRT_XXL
-# define get_kernel_rpl()		0
-#endif
-
 #define IDT_ENTRIES			256
 #define NUM_EXCEPTION_VECTORS		32
 
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index c5d6f17d9b9d..8aa20bc2f1ca 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1413,15 +1413,7 @@ static void generic_identify(struct cpuinfo_x86 *c)
 	 * ESPFIX issue, we can change this.
 	 */
 #ifdef CONFIG_X86_32
-# ifdef CONFIG_PARAVIRT_XXL
-	do {
-		extern void native_iret(void);
-		if (pv_ops.cpu.iret == native_iret)
-			set_cpu_bug(c, X86_BUG_ESPFIX);
-	} while (0);
-# else
 	set_cpu_bug(c, X86_BUG_ESPFIX);
-# endif
 #endif
 }
 
diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
index fdadc37d72af..2ca10b770cff 100644
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -793,7 +793,6 @@ __used __visible void *trampoline_handler(struct pt_regs
*regs)
 	/* fixup registers */
 	regs->cs = __KERNEL_CS;
 #ifdef CONFIG_X86_32
-	regs->cs |= get_kernel_rpl();
 	regs->gs = 0;
 #endif
 	/* We use pt_regs->sp for return address holder. */
diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c
index 40f380461e6d..b8dd113a1284 100644
--- a/arch/x86/kernel/kprobes/opt.c
+++ b/arch/x86/kernel/kprobes/opt.c
@@ -181,7 +181,6 @@ optimized_callback(struct optimized_kprobe *op, struct
pt_regs *regs)
 		/* Save skipped registers */
 		regs->cs = __KERNEL_CS;
 #ifdef CONFIG_X86_32
-		regs->cs |= get_kernel_rpl();
 		regs->gs = 0;
 #endif
 		regs->ip = (unsigned long)op->kp.addr + INT3_INSN_SIZE;
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index de2138ba38e5..e56a144c13b3 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -263,13 +263,8 @@ enum paravirt_lazy_mode paravirt_get_lazy_mode(void)
 struct pv_info pv_info = {
 	.name = "bare hardware",
 #ifdef CONFIG_PARAVIRT_XXL
-	.kernel_rpl = 0,
-	.shared_kernel_pmd = 1,	/* Only used when CONFIG_X86_PAE is set */
-
-#ifdef CONFIG_X86_64
 	.extra_user_64bit_cs = __USER_CS,
 #endif
-#endif
 };
 
 /* 64-bit pagetable entries */
@@ -305,9 +300,7 @@ struct paravirt_patch_template pv_ops = {
 	.cpu.load_idt		= native_load_idt,
 	.cpu.store_tr		= native_store_tr,
 	.cpu.load_tls		= native_load_tls,
-#ifdef CONFIG_X86_64
 	.cpu.load_gs_index	= native_load_gs_index,
-#endif
 	.cpu.write_ldt_entry	= native_write_ldt_entry,
 	.cpu.write_gdt_entry	= native_write_gdt_entry,
 	.cpu.write_idt_entry	= native_write_idt_entry,
@@ -317,9 +310,7 @@ struct paravirt_patch_template pv_ops = {
 
 	.cpu.load_sp0		= native_load_sp0,
 
-#ifdef CONFIG_X86_64
 	.cpu.usergs_sysret64	= native_usergs_sysret64,
-#endif
 	.cpu.iret		= native_iret,
 	.cpu.swapgs		= native_swapgs,
 
@@ -375,18 +366,11 @@ struct paravirt_patch_template pv_ops = {
 	.mmu.ptep_modify_prot_start	= __ptep_modify_prot_start,
 	.mmu.ptep_modify_prot_commit	= __ptep_modify_prot_commit,
 
-#if CONFIG_PGTABLE_LEVELS >= 3
-#ifdef CONFIG_X86_PAE
-	.mmu.set_pte_atomic	= native_set_pte_atomic,
-	.mmu.pte_clear		= native_pte_clear,
-	.mmu.pmd_clear		= native_pmd_clear,
-#endif
 	.mmu.set_pud		= native_set_pud,
 
 	.mmu.pmd_val		= PTE_IDENT,
 	.mmu.make_pmd		= PTE_IDENT,
 
-#if CONFIG_PGTABLE_LEVELS >= 4
 	.mmu.pud_val		= PTE_IDENT,
 	.mmu.make_pud		= PTE_IDENT,
 
@@ -398,8 +382,6 @@ struct paravirt_patch_template pv_ops = {
 
 	.mmu.set_pgd		= native_set_pgd,
 #endif /* CONFIG_PGTABLE_LEVELS >= 5 */
-#endif /* CONFIG_PGTABLE_LEVELS >= 4 */
-#endif /* CONFIG_PGTABLE_LEVELS >= 3 */
 
 	.mmu.pte_val		= PTE_IDENT,
 	.mmu.pgd_val		= PTE_IDENT,
diff --git a/arch/x86/kernel/paravirt_patch.c b/arch/x86/kernel/paravirt_patch.c
index 3eff63c090d2..ace6e334cb39 100644
--- a/arch/x86/kernel/paravirt_patch.c
+++ b/arch/x86/kernel/paravirt_patch.c
@@ -26,14 +26,10 @@ struct patch_xxl {
 	const unsigned char	mmu_read_cr3[3];
 	const unsigned char	mmu_write_cr3[3];
 	const unsigned char	irq_restore_fl[2];
-# ifdef CONFIG_X86_64
 	const unsigned char	cpu_wbinvd[2];
 	const unsigned char	cpu_usergs_sysret64[6];
 	const unsigned char	cpu_swapgs[3];
 	const unsigned char	mov64[3];
-# else
-	const unsigned char	cpu_iret[1];
-# endif
 };
 
 static const struct patch_xxl patch_data_xxl = {
@@ -42,7 +38,6 @@ static const struct patch_xxl patch_data_xxl = {
 	.irq_save_fl		= { 0x9c, 0x58 },	// pushf; pop %[re]ax
 	.mmu_read_cr2		= { 0x0f, 0x20, 0xd0 },	// mov %cr2, %[re]ax
 	.mmu_read_cr3		= { 0x0f, 0x20, 0xd8 },	// mov %cr3, %[re]ax
-# ifdef CONFIG_X86_64
 	.mmu_write_cr3		= { 0x0f, 0x22, 0xdf },	// mov %rdi, %cr3
 	.irq_restore_fl		= { 0x57, 0x9d },	// push %rdi; popfq
 	.cpu_wbinvd		= { 0x0f, 0x09 },	// wbinvd
@@ -50,19 +45,11 @@ static const struct patch_xxl patch_data_xxl = {
 				    0x48, 0x0f, 0x07 },	// swapgs; sysretq
 	.cpu_swapgs		= { 0x0f, 0x01, 0xf8 },	// swapgs
 	.mov64			= { 0x48, 0x89, 0xf8 },	// mov %rdi, %rax
-# else
-	.mmu_write_cr3		= { 0x0f, 0x22, 0xd8 },	// mov %eax, %cr3
-	.irq_restore_fl		= { 0x50, 0x9d },	// push %eax; popf
-	.cpu_iret		= { 0xcf },		// iret
-# endif
 };
 
 unsigned int paravirt_patch_ident_64(void *insn_buff, unsigned int len)
 {
-#ifdef CONFIG_X86_64
 	return PATCH(xxl, mov64, insn_buff, len);
-#endif
-	return 0;
 }
 # endif /* CONFIG_PARAVIRT_XXL */
 
@@ -98,13 +85,9 @@ unsigned int native_patch(u8 type, void *insn_buff, unsigned
long addr,
 	PATCH_CASE(mmu, read_cr3, xxl, insn_buff, len);
 	PATCH_CASE(mmu, write_cr3, xxl, insn_buff, len);
 
-# ifdef CONFIG_X86_64
 	PATCH_CASE(cpu, usergs_sysret64, xxl, insn_buff, len);
 	PATCH_CASE(cpu, swapgs, xxl, insn_buff, len);
 	PATCH_CASE(cpu, wbinvd, xxl, insn_buff, len);
-# else
-	PATCH_CASE(cpu, iret, xxl, insn_buff, len);
-# endif
 #endif
 
 #ifdef CONFIG_PARAVIRT_SPINLOCKS
diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 22e741e0b10c..41485a8a6dcf 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -1014,8 +1014,6 @@ void __init xen_setup_vcpu_info_placement(void)
 }
 
 static const struct pv_info xen_info __initconst = {
-	.shared_kernel_pmd = 0,
-
 	.extra_user_64bit_cs = FLAT_USER_CS64,
 	.name = "Xen",
 };
@@ -1314,10 +1312,6 @@ asmlinkage __visible void __init xen_start_kernel(void)
 				   xen_start_info->nr_pages);
 	xen_reserve_special_pages();
 
-	/* keep using Xen gdt for now; no urgent need to change it */
-
-	pv_info.kernel_rpl = 0;
-
 	/*
 	 * We used to do this in xen_arch_setup, but that is too late
 	 * on AMD were early_cpu_init (run before ->arch_setup()) calls
-- 
2.26.2

Juergen Gross

2020-Aug-15 10:06 UTC

head link

[PATCH v4 2/6] x86/paravirt: cleanup paravirt macros

Some paravirt macros are no longer used, delete them.

Signed-off-by: Juergen Gross <jgross at suse.com>
---
 arch/x86/include/asm/paravirt.h | 15 ---------------
 1 file changed, 15 deletions(-)

diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index 25c7a73461f6..e02c409fa054 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -586,16 +586,9 @@ bool __raw_callee_save___native_vcpu_is_preempted(long
cpu);
 #endif /* SMP && PARAVIRT_SPINLOCKS */
 
 #ifdef CONFIG_X86_32
-#define PV_SAVE_REGS "pushl %ecx; pushl %edx;"
-#define PV_RESTORE_REGS "popl %edx; popl %ecx;"
-
 /* save and restore all caller-save registers, except return value */
 #define PV_SAVE_ALL_CALLER_REGS		"pushl %ecx;"
 #define PV_RESTORE_ALL_CALLER_REGS	"popl  %ecx;"
-
-#define PV_FLAGS_ARG "0"
-#define PV_EXTRA_CLOBBERS
-#define PV_VEXTRA_CLOBBERS
 #else
 /* save and restore all caller-save registers, except return value */
 #define PV_SAVE_ALL_CALLER_REGS						\
@@ -616,14 +609,6 @@ bool __raw_callee_save___native_vcpu_is_preempted(long
cpu);
 	"pop %rsi;"							\
 	"pop %rdx;"							\
 	"pop %rcx;"
-
-/* We save some registers, but all of them, that's too much. We clobber all
- * caller saved registers but the argument parameter */
-#define PV_SAVE_REGS "pushq %%rdi;"
-#define PV_RESTORE_REGS "popq %%rdi;"
-#define PV_EXTRA_CLOBBERS EXTRA_CLOBBERS, "rcx" , "rdx",
"rsi"
-#define PV_VEXTRA_CLOBBERS EXTRA_CLOBBERS, "rdi", "rcx" ,
"rdx", "rsi"
-#define PV_FLAGS_ARG "D"
 #endif
 
 /*
-- 
2.26.2

Juergen Gross

2020-Aug-15 10:06 UTC

head link

[PATCH v4 5/6] x86/paravirt: remove set_pte_at pv-op

On x86 set_pte_at() is now always falling back to set_pte(). So instead
of having this fallback after the paravirt maze just drop the
set_pte_at paravirt operation and let set_pte_at() use the set_pte()
function directly.

Signed-off-by: Juergen Gross <jgross at suse.com>
---
 arch/x86/include/asm/paravirt.h       |  8 +-------
 arch/x86/include/asm/paravirt_types.h |  2 --
 arch/x86/include/asm/pgtable.h        |  7 +++----
 arch/x86/kernel/paravirt.c            |  1 -
 arch/x86/xen/mmu_pv.c                 |  8 --------
 include/trace/events/xen.h            | 20 --------------------
 6 files changed, 4 insertions(+), 42 deletions(-)

diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index e02c409fa054..f0464b88ea1e 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -412,12 +412,6 @@ static inline void set_pte(pte_t *ptep, pte_t pte)
 	PVOP_VCALL2(mmu.set_pte, ptep, pte.pte);
 }
 
-static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
-			      pte_t *ptep, pte_t pte)
-{
-	PVOP_VCALL4(mmu.set_pte_at, mm, addr, ptep, pte.pte);
-}
-
 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
 {
 	PVOP_VCALL2(mmu.set_pmd, pmdp, native_pmd_val(pmd));
@@ -510,7 +504,7 @@ static inline void set_pte_atomic(pte_t *ptep, pte_t pte)
 static inline void pte_clear(struct mm_struct *mm, unsigned long addr,
 			     pte_t *ptep)
 {
-	set_pte_at(mm, addr, ptep, __pte(0));
+	set_pte(ptep, __pte(0));
 }
 
 static inline void pmd_clear(pmd_t *pmdp)
diff --git a/arch/x86/include/asm/paravirt_types.h
b/arch/x86/include/asm/paravirt_types.h
index f27c3febaa6e..0fad9f61c76a 100644
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -242,8 +242,6 @@ struct pv_mmu_ops {
 
 	/* Pagetable manipulation functions */
 	void (*set_pte)(pte_t *ptep, pte_t pteval);
-	void (*set_pte_at)(struct mm_struct *mm, unsigned long addr,
-			   pte_t *ptep, pte_t pteval);
 	void (*set_pmd)(pmd_t *pmdp, pmd_t pmdval);
 
 	pte_t (*ptep_modify_prot_start)(struct vm_area_struct *vma, unsigned long
addr,
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index b836138ce852..7414b416779b 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -63,7 +63,6 @@ extern pmdval_t early_pmd_flags;
 #include <asm/paravirt.h>
 #else  /* !CONFIG_PARAVIRT_XXL */
 #define set_pte(ptep, pte)		native_set_pte(ptep, pte)
-#define set_pte_at(mm, addr, ptep, pte)	native_set_pte_at(mm, addr, ptep, pte)
 
 #define set_pte_atomic(ptep, pte)					\
 	native_set_pte_atomic(ptep, pte)
@@ -1033,10 +1032,10 @@ static inline pud_t
native_local_pudp_get_and_clear(pud_t *pudp)
 	return res;
 }
 
-static inline void native_set_pte_at(struct mm_struct *mm, unsigned long addr,
-				     pte_t *ptep , pte_t pte)
+static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
+			      pte_t *ptep, pte_t pte)
 {
-	native_set_pte(ptep, pte);
+	set_pte(ptep, pte);
 }
 
 static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index e56a144c13b3..6c3407ba6ee9 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -360,7 +360,6 @@ struct paravirt_patch_template pv_ops = {
 	.mmu.release_p4d	= paravirt_nop,
 
 	.mmu.set_pte		= native_set_pte,
-	.mmu.set_pte_at		= native_set_pte_at,
 	.mmu.set_pmd		= native_set_pmd,
 
 	.mmu.ptep_modify_prot_start	= __ptep_modify_prot_start,
diff --git a/arch/x86/xen/mmu_pv.c b/arch/x86/xen/mmu_pv.c
index 3273c985d3dd..eda78144c000 100644
--- a/arch/x86/xen/mmu_pv.c
+++ b/arch/x86/xen/mmu_pv.c
@@ -285,13 +285,6 @@ static void xen_set_pte(pte_t *ptep, pte_t pteval)
 	__xen_set_pte(ptep, pteval);
 }
 
-static void xen_set_pte_at(struct mm_struct *mm, unsigned long addr,
-		    pte_t *ptep, pte_t pteval)
-{
-	trace_xen_mmu_set_pte_at(mm, addr, ptep, pteval);
-	__xen_set_pte(ptep, pteval);
-}
-
 pte_t xen_ptep_modify_prot_start(struct vm_area_struct *vma,
 				 unsigned long addr, pte_t *ptep)
 {
@@ -2105,7 +2098,6 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = {
 	.release_pmd = xen_release_pmd_init,
 
 	.set_pte = xen_set_pte_init,
-	.set_pte_at = xen_set_pte_at,
 	.set_pmd = xen_set_pmd_hyper,
 
 	.ptep_modify_prot_start = __ptep_modify_prot_start,
diff --git a/include/trace/events/xen.h b/include/trace/events/xen.h
index a5ccfa67bc5c..3b61b587e137 100644
--- a/include/trace/events/xen.h
+++ b/include/trace/events/xen.h
@@ -153,26 +153,6 @@ DECLARE_EVENT_CLASS(xen_mmu__set_pte,
 
 DEFINE_XEN_MMU_SET_PTE(xen_mmu_set_pte);
 
-TRACE_EVENT(xen_mmu_set_pte_at,
-	    TP_PROTO(struct mm_struct *mm, unsigned long addr,
-		     pte_t *ptep, pte_t pteval),
-	    TP_ARGS(mm, addr, ptep, pteval),
-	    TP_STRUCT__entry(
-		    __field(struct mm_struct *, mm)
-		    __field(unsigned long, addr)
-		    __field(pte_t *, ptep)
-		    __field(pteval_t, pteval)
-		    ),
-	    TP_fast_assign(__entry->mm = mm;
-			   __entry->addr = addr;
-			   __entry->ptep = ptep;
-			   __entry->pteval = pteval.pte),
-	    TP_printk("mm %p addr %lx ptep %p pteval %0*llx (raw %0*llx)",
-		      __entry->mm, __entry->addr, __entry->ptep,
-		      (int)sizeof(pteval_t) * 2, (unsigned long
long)pte_val(native_make_pte(__entry->pteval)),
-		      (int)sizeof(pteval_t) * 2, (unsigned long long)__entry->pteval)
-	);
-
 TRACE_DEFINE_SIZEOF(pmdval_t);
 
 TRACE_EVENT(xen_mmu_set_pmd,
-- 
2.26.2

Juergen Gross

2020-Aug-15 10:06 UTC

head link

[PATCH v4 6/6] x86/paravirt: avoid needless paravirt step clearing page table entries

pte_clear() et al are based on tw0 paravirt steps today: one step to
create a page table entry with all zeroes, and one step to write this
entry value.

Drop the first step as it is completely useless.

Signed-off-by: Juergen Gross <jgross at suse.com>
---
 arch/x86/include/asm/paravirt.h | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index f0464b88ea1e..d25cc6830e89 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -448,7 +448,7 @@ static inline pudval_t pud_val(pud_t pud)
 
 static inline void pud_clear(pud_t *pudp)
 {
-	set_pud(pudp, __pud(0));
+	set_pud(pudp, native_make_pud(0));
 }
 
 static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
@@ -485,15 +485,15 @@ static inline void __set_pgd(pgd_t *pgdp, pgd_t pgd)
 } while (0)
 
 #define pgd_clear(pgdp) do {						\
-	if (pgtable_l5_enabled())						\
-		set_pgd(pgdp, __pgd(0));				\
+	if (pgtable_l5_enabled())					\
+		set_pgd(pgdp, native_make_pgd(0));			\
 } while (0)
 
 #endif  /* CONFIG_PGTABLE_LEVELS == 5 */
 
 static inline void p4d_clear(p4d_t *p4dp)
 {
-	set_p4d(p4dp, __p4d(0));
+	set_p4d(p4dp, native_make_p4d(0));
 }
 
 static inline void set_pte_atomic(pte_t *ptep, pte_t pte)
@@ -504,12 +504,12 @@ static inline void set_pte_atomic(pte_t *ptep, pte_t pte)
 static inline void pte_clear(struct mm_struct *mm, unsigned long addr,
 			     pte_t *ptep)
 {
-	set_pte(ptep, __pte(0));
+	set_pte(ptep, native_make_pte(0));
 }
 
 static inline void pmd_clear(pmd_t *pmdp)
 {
-	set_pmd(pmdp, __pmd(0));
+	set_pmd(pmdp, native_make_pmd(0));
 }
 
 #define  __HAVE_ARCH_START_CONTEXT_SWITCH
-- 
2.26.2

boris.ostrovsky at oracle.com

2020-Aug-16 18:37 UTC

head link

[PATCH v4 1/6] x86/paravirt: remove 32-bit support from PARAVIRT_XXL

On 8/15/20 6:06 AM, Juergen Gross wrote:> The last 32-bit user of stuff under CONFIG_PARAVIRT_XXL is gone.
>
> Remove 32-bit specific parts.
>
> Signed-off-by: Juergen Gross <jgross at suse.com>

Reviewed-by: Boris Ostrovsky <bortis.ostrovsky at oracle.com>


(There is another '#ifdef CONFIG_X86_64' in paravirt.h, at the bottom,
that can be removed as well)

boris.ostrovsky at oracle.com

2020-Aug-16 18:44 UTC

head link

[PATCH v4 5/6] x86/paravirt: remove set_pte_at pv-op

On 8/15/20 6:06 AM, Juergen Gross wrote:> On x86 set_pte_at() is now always falling back to set_pte(). So instead
> of having this fallback after the paravirt maze just drop the
> set_pte_at paravirt operation and let set_pte_at() use the set_pte()
> function directly.
>
> Signed-off-by: Juergen Gross <jgross at suse.com>

Reviewed-by: Boris Ostrovsky <boris.ostrovsky at oracle.com>

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