From patchwork Fri Aug 7 08:38:20 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?SsO8cmdlbiBHcm/Dnw==?= X-Patchwork-Id: 11705133 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 545B614DD for ; Fri, 7 Aug 2020 08:39:31 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 263D522CAE for ; Fri, 7 Aug 2020 08:39:31 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 263D522CAE Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1k3xtg-0006vm-PC; Fri, 07 Aug 2020 08:38:40 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1k3xtf-0006sY-Jr for xen-devel@lists.xenproject.org; Fri, 07 Aug 2020 08:38:39 +0000 X-Inumbo-ID: 49129e61-96ff-441b-8e45-79e168c68078 Received: from mx2.suse.de (unknown [195.135.220.15]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id 49129e61-96ff-441b-8e45-79e168c68078; Fri, 07 Aug 2020 08:38:32 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 1CD96B628; Fri, 7 Aug 2020 08:38:49 +0000 (UTC) From: Juergen Gross To: xen-devel@lists.xenproject.org, x86@kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 1/7] x86/xen: remove 32-bit Xen PV guest support Date: Fri, 7 Aug 2020 10:38:20 +0200 Message-Id: <20200807083826.16794-2-jgross@suse.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200807083826.16794-1-jgross@suse.com> References: <20200807083826.16794-1-jgross@suse.com> MIME-Version: 1.0 X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Juergen Gross , Stefano Stabellini , Ingo Molnar , Borislav Petkov , Andy Lutomirski , "H. Peter Anvin" , Thomas Gleixner , Boris Ostrovsky Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" Xen is requiring 64-bit machines today and since Xen 4.14 it can be built without 32-bit PV guest support. There is no need to carry the burden of 32-bit PV guest support in the kernel any longer, as new guests can be either HVM or PVH, or they can use a 64 bit kernel. Remove the 32-bit Xen PV support from the kernel. Signed-off-by: Juergen Gross Reviewed-by: Boris Ostrovsky --- arch/x86/entry/entry_32.S | 109 +-------- arch/x86/entry/vdso/vdso32/note.S | 30 --- arch/x86/include/asm/proto.h | 2 +- arch/x86/include/asm/segment.h | 2 +- arch/x86/kernel/head_32.S | 31 --- arch/x86/xen/Kconfig | 3 +- arch/x86/xen/apic.c | 17 -- arch/x86/xen/enlighten_pv.c | 63 +----- arch/x86/xen/mmu_pv.c | 352 ++++-------------------------- arch/x86/xen/p2m.c | 6 +- arch/x86/xen/setup.c | 36 +-- arch/x86/xen/smp_pv.c | 18 -- arch/x86/xen/vdso.h | 6 - arch/x86/xen/xen-asm.S | 14 -- arch/x86/xen/xen-asm_32.S | 185 ---------------- arch/x86/xen/xen-head.S | 6 - drivers/xen/Kconfig | 4 +- 17 files changed, 51 insertions(+), 833 deletions(-) delete mode 100644 arch/x86/xen/vdso.h delete mode 100644 arch/x86/xen/xen-asm_32.S diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S index 29b7d52143e9..df8c017e6161 100644 --- a/arch/x86/entry/entry_32.S +++ b/arch/x86/entry/entry_32.S @@ -449,8 +449,6 @@ .macro SWITCH_TO_KERNEL_STACK - ALTERNATIVE "", "jmp .Lend_\@", X86_FEATURE_XENPV - BUG_IF_WRONG_CR3 SWITCH_TO_KERNEL_CR3 scratch_reg=%eax @@ -599,8 +597,6 @@ */ .macro SWITCH_TO_ENTRY_STACK - ALTERNATIVE "", "jmp .Lend_\@", X86_FEATURE_XENPV - /* Bytes to copy */ movl $PTREGS_SIZE, %ecx @@ -872,17 +868,6 @@ SYM_ENTRY(__begin_SYSENTER_singlestep_region, SYM_L_GLOBAL, SYM_A_NONE) * will ignore all of the single-step traps generated in this range. */ -#ifdef CONFIG_XEN_PV -/* - * Xen doesn't set %esp to be precisely what the normal SYSENTER - * entry point expects, so fix it up before using the normal path. - */ -SYM_CODE_START(xen_sysenter_target) - addl $5*4, %esp /* remove xen-provided frame */ - jmp .Lsysenter_past_esp -SYM_CODE_END(xen_sysenter_target) -#endif - /* * 32-bit SYSENTER entry. * @@ -965,9 +950,8 @@ SYM_FUNC_START(entry_SYSENTER_32) movl %esp, %eax call do_SYSENTER_32 - /* XEN PV guests always use IRET path */ - ALTERNATIVE "testl %eax, %eax; jz .Lsyscall_32_done", \ - "jmp .Lsyscall_32_done", X86_FEATURE_XENPV + testl %eax, %eax + jz .Lsyscall_32_done STACKLEAK_ERASE @@ -1165,95 +1149,6 @@ SYM_FUNC_END(entry_INT80_32) #endif .endm -#ifdef CONFIG_PARAVIRT -SYM_CODE_START(native_iret) - iret - _ASM_EXTABLE(native_iret, asm_iret_error) -SYM_CODE_END(native_iret) -#endif - -#ifdef CONFIG_XEN_PV -/* - * See comment in entry_64.S for further explanation - * - * Note: This is not an actual IDT entry point. It's a XEN specific entry - * point and therefore named to match the 64-bit trampoline counterpart. - */ -SYM_FUNC_START(xen_asm_exc_xen_hypervisor_callback) - /* - * Check to see if we got the event in the critical - * region in xen_iret_direct, after we've reenabled - * events and checked for pending events. This simulates - * iret instruction's behaviour where it delivers a - * pending interrupt when enabling interrupts: - */ - cmpl $xen_iret_start_crit, (%esp) - jb 1f - cmpl $xen_iret_end_crit, (%esp) - jae 1f - call xen_iret_crit_fixup -1: - pushl $-1 /* orig_ax = -1 => not a system call */ - SAVE_ALL - ENCODE_FRAME_POINTER - - mov %esp, %eax - call xen_pv_evtchn_do_upcall - jmp handle_exception_return -SYM_FUNC_END(xen_asm_exc_xen_hypervisor_callback) - -/* - * Hypervisor uses this for application faults while it executes. - * We get here for two reasons: - * 1. Fault while reloading DS, ES, FS or GS - * 2. Fault while executing IRET - * Category 1 we fix up by reattempting the load, and zeroing the segment - * register if the load fails. - * Category 2 we fix up by jumping to do_iret_error. We cannot use the - * normal Linux return path in this case because if we use the IRET hypercall - * to pop the stack frame we end up in an infinite loop of failsafe callbacks. - * We distinguish between categories by maintaining a status value in EAX. - */ -SYM_FUNC_START(xen_failsafe_callback) - pushl %eax - movl $1, %eax -1: mov 4(%esp), %ds -2: mov 8(%esp), %es -3: mov 12(%esp), %fs -4: mov 16(%esp), %gs - /* EAX == 0 => Category 1 (Bad segment) - EAX != 0 => Category 2 (Bad IRET) */ - testl %eax, %eax - popl %eax - lea 16(%esp), %esp - jz 5f - jmp asm_iret_error -5: pushl $-1 /* orig_ax = -1 => not a system call */ - SAVE_ALL - ENCODE_FRAME_POINTER - jmp handle_exception_return - -.section .fixup, "ax" -6: xorl %eax, %eax - movl %eax, 4(%esp) - jmp 1b -7: xorl %eax, %eax - movl %eax, 8(%esp) - jmp 2b -8: xorl %eax, %eax - movl %eax, 12(%esp) - jmp 3b -9: xorl %eax, %eax - movl %eax, 16(%esp) - jmp 4b -.previous - _ASM_EXTABLE(1b, 6b) - _ASM_EXTABLE(2b, 7b) - _ASM_EXTABLE(3b, 8b) - _ASM_EXTABLE(4b, 9b) -SYM_FUNC_END(xen_failsafe_callback) -#endif /* CONFIG_XEN_PV */ - SYM_CODE_START_LOCAL_NOALIGN(handle_exception) /* the function address is in %gs's slot on the stack */ SAVE_ALL switch_stacks=1 skip_gs=1 unwind_espfix=1 diff --git a/arch/x86/entry/vdso/vdso32/note.S b/arch/x86/entry/vdso/vdso32/note.S index e78047d119f6..2cbd39939dc6 100644 --- a/arch/x86/entry/vdso/vdso32/note.S +++ b/arch/x86/entry/vdso/vdso32/note.S @@ -16,33 +16,3 @@ ELFNOTE_START(Linux, 0, "a") ELFNOTE_END BUILD_SALT - -#ifdef CONFIG_XEN -/* - * Add a special note telling glibc's dynamic linker a fake hardware - * flavor that it will use to choose the search path for libraries in the - * same way it uses real hardware capabilities like "mmx". - * We supply "nosegneg" as the fake capability, to indicate that we - * do not like negative offsets in instructions using segment overrides, - * since we implement those inefficiently. This makes it possible to - * install libraries optimized to avoid those access patterns in someplace - * like /lib/i686/tls/nosegneg. Note that an /etc/ld.so.conf.d/file - * corresponding to the bits here is needed to make ldconfig work right. - * It should contain: - * hwcap 1 nosegneg - * to match the mapping of bit to name that we give here. - * - * At runtime, the fake hardware feature will be considered to be present - * if its bit is set in the mask word. So, we start with the mask 0, and - * at boot time we set VDSO_NOTE_NONEGSEG_BIT if running under Xen. - */ - -#include "../../xen/vdso.h" /* Defines VDSO_NOTE_NONEGSEG_BIT. */ - -ELFNOTE_START(GNU, 2, "a") - .long 1 /* ncaps */ -VDSO32_NOTE_MASK: /* Symbol used by arch/x86/xen/setup.c */ - .long 0 /* mask */ - .byte VDSO_NOTE_NONEGSEG_BIT; .asciz "nosegneg" /* bit, name */ -ELFNOTE_END -#endif diff --git a/arch/x86/include/asm/proto.h b/arch/x86/include/asm/proto.h index 6e81788a30c1..28996fe19301 100644 --- a/arch/x86/include/asm/proto.h +++ b/arch/x86/include/asm/proto.h @@ -25,7 +25,7 @@ void entry_SYSENTER_compat(void); void __end_entry_SYSENTER_compat(void); void entry_SYSCALL_compat(void); void entry_INT80_compat(void); -#if defined(CONFIG_X86_64) && defined(CONFIG_XEN_PV) +#ifdef CONFIG_XEN_PV void xen_entry_INT80_compat(void); #endif #endif diff --git a/arch/x86/include/asm/segment.h b/arch/x86/include/asm/segment.h index 6669164abadc..9646c300f128 100644 --- a/arch/x86/include/asm/segment.h +++ b/arch/x86/include/asm/segment.h @@ -301,7 +301,7 @@ static inline void vdso_read_cpunode(unsigned *cpu, unsigned *node) extern const char early_idt_handler_array[NUM_EXCEPTION_VECTORS][EARLY_IDT_HANDLER_SIZE]; extern void early_ignore_irq(void); -#if defined(CONFIG_X86_64) && defined(CONFIG_XEN_PV) +#ifdef CONFIG_XEN_PV extern const char xen_early_idt_handler_array[NUM_EXCEPTION_VECTORS][XEN_EARLY_IDT_HANDLER_SIZE]; #endif diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S index f66a6b90f954..7ed84c282233 100644 --- a/arch/x86/kernel/head_32.S +++ b/arch/x86/kernel/head_32.S @@ -134,38 +134,7 @@ SYM_CODE_START(startup_32) movl %eax,pa(initial_page_table+0xffc) #endif -#ifdef CONFIG_PARAVIRT - /* This is can only trip for a broken bootloader... */ - cmpw $0x207, pa(boot_params + BP_version) - jb .Ldefault_entry - - /* Paravirt-compatible boot parameters. Look to see what architecture - we're booting under. */ - movl pa(boot_params + BP_hardware_subarch), %eax - cmpl $num_subarch_entries, %eax - jae .Lbad_subarch - - movl pa(subarch_entries)(,%eax,4), %eax - subl $__PAGE_OFFSET, %eax - jmp *%eax - -.Lbad_subarch: -SYM_INNER_LABEL_ALIGN(xen_entry, SYM_L_WEAK) - /* Unknown implementation; there's really - nothing we can do at this point. */ - ud2a - - __INITDATA - -subarch_entries: - .long .Ldefault_entry /* normal x86/PC */ - .long xen_entry /* Xen hypervisor */ - .long .Ldefault_entry /* Moorestown MID */ -num_subarch_entries = (. - subarch_entries) / 4 -.previous -#else jmp .Ldefault_entry -#endif /* CONFIG_PARAVIRT */ SYM_CODE_END(startup_32) #ifdef CONFIG_HOTPLUG_CPU diff --git a/arch/x86/xen/Kconfig b/arch/x86/xen/Kconfig index 1aded63a95cb..218acbd5c7a0 100644 --- a/arch/x86/xen/Kconfig +++ b/arch/x86/xen/Kconfig @@ -19,6 +19,7 @@ config XEN_PV bool "Xen PV guest support" default y depends on XEN + depends on X86_64 select PARAVIRT_XXL select XEN_HAVE_PVMMU select XEN_HAVE_VPMU @@ -50,7 +51,7 @@ config XEN_PVHVM_SMP config XEN_512GB bool "Limit Xen pv-domain memory to 512GB" - depends on XEN_PV && X86_64 + depends on XEN_PV default y help Limit paravirtualized user domains to 512GB of RAM. diff --git a/arch/x86/xen/apic.c b/arch/x86/xen/apic.c index 5e53bfbe5823..ea6e9c54da9d 100644 --- a/arch/x86/xen/apic.c +++ b/arch/x86/xen/apic.c @@ -58,10 +58,6 @@ static u32 xen_apic_read(u32 reg) if (reg == APIC_LVR) return 0x14; -#ifdef CONFIG_X86_32 - if (reg == APIC_LDR) - return SET_APIC_LOGICAL_ID(1UL << smp_processor_id()); -#endif if (reg != APIC_ID) return 0; @@ -127,14 +123,6 @@ static int xen_phys_pkg_id(int initial_apic_id, int index_msb) return initial_apic_id >> index_msb; } -#ifdef CONFIG_X86_32 -static int xen_x86_32_early_logical_apicid(int cpu) -{ - /* Match with APIC_LDR read. Otherwise setup_local_APIC complains. */ - return 1 << cpu; -} -#endif - static void xen_noop(void) { } @@ -197,11 +185,6 @@ static struct apic xen_pv_apic = { .icr_write = xen_apic_icr_write, .wait_icr_idle = xen_noop, .safe_wait_icr_idle = xen_safe_apic_wait_icr_idle, - -#ifdef CONFIG_X86_32 - /* generic_processor_info and setup_local_APIC. */ - .x86_32_early_logical_apicid = xen_x86_32_early_logical_apicid, -#endif }; static void __init xen_apic_check(void) diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c index 2aab43a13a8c..7d90b3da8bb4 100644 --- a/arch/x86/xen/enlighten_pv.c +++ b/arch/x86/xen/enlighten_pv.c @@ -119,14 +119,6 @@ static void __init xen_banner(void) printk(KERN_INFO "Xen version: %d.%d%s%s\n", version >> 16, version & 0xffff, extra.extraversion, xen_feature(XENFEAT_mmu_pt_update_preserve_ad) ? " (preserve-AD)" : ""); - -#ifdef CONFIG_X86_32 - pr_warn("WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING!\n" - "Support for running as 32-bit PV-guest under Xen will soon be removed\n" - "from the Linux kernel!\n" - "Please use either a 64-bit kernel or switch to HVM or PVH mode!\n" - "WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING!\n"); -#endif } static void __init xen_pv_init_platform(void) @@ -538,30 +530,12 @@ static void load_TLS_descriptor(struct thread_struct *t, static void xen_load_tls(struct thread_struct *t, unsigned int cpu) { /* - * XXX sleazy hack: If we're being called in a lazy-cpu zone - * and lazy gs handling is enabled, it means we're in a - * context switch, and %gs has just been saved. This means we - * can zero it out to prevent faults on exit from the - * hypervisor if the next process has no %gs. Either way, it - * has been saved, and the new value will get loaded properly. - * This will go away as soon as Xen has been modified to not - * save/restore %gs for normal hypercalls. - * - * On x86_64, this hack is not used for %gs, because gs points - * to KERNEL_GS_BASE (and uses it for PDA references), so we - * must not zero %gs on x86_64 - * - * For x86_64, we need to zero %fs, otherwise we may get an + * In lazy mode we need to zero %fs, otherwise we may get an * exception between the new %fs descriptor being loaded and * %fs being effectively cleared at __switch_to(). */ - if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU) { -#ifdef CONFIG_X86_32 - lazy_load_gs(0); -#else + if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU) loadsegment(fs, 0); -#endif - } xen_mc_batch(); @@ -572,13 +546,11 @@ static void xen_load_tls(struct thread_struct *t, unsigned int cpu) xen_mc_issue(PARAVIRT_LAZY_CPU); } -#ifdef CONFIG_X86_64 static void xen_load_gs_index(unsigned int idx) { if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL, idx)) BUG(); } -#endif static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum, const void *ptr) @@ -597,7 +569,6 @@ static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum, preempt_enable(); } -#ifdef CONFIG_X86_64 void noist_exc_debug(struct pt_regs *regs); DEFINE_IDTENTRY_RAW(xenpv_exc_nmi) @@ -697,7 +668,6 @@ static bool __ref get_trap_addr(void **addr, unsigned int ist) return true; } -#endif static int cvt_gate_to_trap(int vector, const gate_desc *val, struct trap_info *info) @@ -710,10 +680,8 @@ static int cvt_gate_to_trap(int vector, const gate_desc *val, info->vector = vector; addr = gate_offset(val); -#ifdef CONFIG_X86_64 if (!get_trap_addr((void **)&addr, val->bits.ist)) return 0; -#endif /* CONFIG_X86_64 */ info->address = addr; info->cs = gate_segment(val); @@ -958,15 +926,12 @@ static u64 xen_read_msr_safe(unsigned int msr, int *err) static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high) { int ret; -#ifdef CONFIG_X86_64 unsigned int which; u64 base; -#endif ret = 0; switch (msr) { -#ifdef CONFIG_X86_64 case MSR_FS_BASE: which = SEGBASE_FS; goto set; case MSR_KERNEL_GS_BASE: which = SEGBASE_GS_USER; goto set; case MSR_GS_BASE: which = SEGBASE_GS_KERNEL; goto set; @@ -976,7 +941,6 @@ static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high) if (HYPERVISOR_set_segment_base(which, base) != 0) ret = -EIO; break; -#endif case MSR_STAR: case MSR_CSTAR: @@ -1058,9 +1022,7 @@ void __init xen_setup_vcpu_info_placement(void) static const struct pv_info xen_info __initconst = { .shared_kernel_pmd = 0, -#ifdef CONFIG_X86_64 .extra_user_64bit_cs = FLAT_USER_CS64, -#endif .name = "Xen", }; @@ -1086,18 +1048,14 @@ static const struct pv_cpu_ops xen_cpu_ops __initconst = { .read_pmc = xen_read_pmc, .iret = xen_iret, -#ifdef CONFIG_X86_64 .usergs_sysret64 = xen_sysret64, -#endif .load_tr_desc = paravirt_nop, .set_ldt = xen_set_ldt, .load_gdt = xen_load_gdt, .load_idt = xen_load_idt, .load_tls = xen_load_tls, -#ifdef CONFIG_X86_64 .load_gs_index = xen_load_gs_index, -#endif .alloc_ldt = xen_alloc_ldt, .free_ldt = xen_free_ldt, @@ -1364,13 +1322,8 @@ asmlinkage __visible void __init xen_start_kernel(void) /* keep using Xen gdt for now; no urgent need to change it */ -#ifdef CONFIG_X86_32 - pv_info.kernel_rpl = 1; - if (xen_feature(XENFEAT_supervisor_mode_kernel)) - pv_info.kernel_rpl = 0; -#else pv_info.kernel_rpl = 0; -#endif + /* set the limit of our address space */ xen_reserve_top(); @@ -1384,12 +1337,6 @@ asmlinkage __visible void __init xen_start_kernel(void) if (rc != 0) xen_raw_printk("physdev_op failed %d\n", rc); -#ifdef CONFIG_X86_32 - /* set up basic CPUID stuff */ - cpu_detect(&new_cpu_data); - set_cpu_cap(&new_cpu_data, X86_FEATURE_FPU); - new_cpu_data.x86_capability[CPUID_1_EDX] = cpuid_edx(1); -#endif if (xen_start_info->mod_start) { if (xen_start_info->flags & SIF_MOD_START_PFN) @@ -1458,12 +1405,8 @@ asmlinkage __visible void __init xen_start_kernel(void) xen_efi_init(&boot_params); /* Start the world */ -#ifdef CONFIG_X86_32 - i386_start_kernel(); -#else cr4_init_shadow(); /* 32b kernel does this in i386_start_kernel() */ x86_64_start_reservations((char *)__pa_symbol(&boot_params)); -#endif } static int xen_cpu_up_prepare_pv(unsigned int cpu) diff --git a/arch/x86/xen/mmu_pv.c b/arch/x86/xen/mmu_pv.c index a58d9c69807a..1f9500d0b839 100644 --- a/arch/x86/xen/mmu_pv.c +++ b/arch/x86/xen/mmu_pv.c @@ -86,19 +86,8 @@ #include "mmu.h" #include "debugfs.h" -#ifdef CONFIG_X86_32 -/* - * Identity map, in addition to plain kernel map. This needs to be - * large enough to allocate page table pages to allocate the rest. - * Each page can map 2MB. - */ -#define LEVEL1_IDENT_ENTRIES (PTRS_PER_PTE * 4) -static RESERVE_BRK_ARRAY(pte_t, level1_ident_pgt, LEVEL1_IDENT_ENTRIES); -#endif -#ifdef CONFIG_X86_64 /* l3 pud for userspace vsyscall mapping */ static pud_t level3_user_vsyscall[PTRS_PER_PUD] __page_aligned_bss; -#endif /* CONFIG_X86_64 */ /* * Protects atomic reservation decrease/increase against concurrent increases. @@ -280,10 +269,7 @@ static inline void __xen_set_pte(pte_t *ptep, pte_t pteval) if (!xen_batched_set_pte(ptep, pteval)) { /* * Could call native_set_pte() here and trap and - * emulate the PTE write but with 32-bit guests this - * needs two traps (one for each of the two 32-bit - * words in the PTE) so do one hypercall directly - * instead. + * emulate the PTE write, but a hypercall is much cheaper. */ struct mmu_update u; @@ -439,26 +425,6 @@ static void xen_set_pud(pud_t *ptr, pud_t val) xen_set_pud_hyper(ptr, val); } -#ifdef CONFIG_X86_PAE -static void xen_set_pte_atomic(pte_t *ptep, pte_t pte) -{ - trace_xen_mmu_set_pte_atomic(ptep, pte); - __xen_set_pte(ptep, pte); -} - -static void xen_pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) -{ - trace_xen_mmu_pte_clear(mm, addr, ptep); - __xen_set_pte(ptep, native_make_pte(0)); -} - -static void xen_pmd_clear(pmd_t *pmdp) -{ - trace_xen_mmu_pmd_clear(pmdp); - set_pmd(pmdp, __pmd(0)); -} -#endif /* CONFIG_X86_PAE */ - __visible pmd_t xen_make_pmd(pmdval_t pmd) { pmd = pte_pfn_to_mfn(pmd); @@ -466,7 +432,6 @@ __visible pmd_t xen_make_pmd(pmdval_t pmd) } PV_CALLEE_SAVE_REGS_THUNK(xen_make_pmd); -#ifdef CONFIG_X86_64 __visible pudval_t xen_pud_val(pud_t pud) { return pte_mfn_to_pfn(pud.pud); @@ -571,7 +536,6 @@ __visible p4d_t xen_make_p4d(p4dval_t p4d) } PV_CALLEE_SAVE_REGS_THUNK(xen_make_p4d); #endif /* CONFIG_PGTABLE_LEVELS >= 5 */ -#endif /* CONFIG_X86_64 */ static int xen_pmd_walk(struct mm_struct *mm, pmd_t *pmd, int (*func)(struct mm_struct *mm, struct page *, enum pt_level), @@ -636,11 +600,8 @@ static int xen_p4d_walk(struct mm_struct *mm, p4d_t *p4d, * will be STACK_TOP_MAX, but at boot we need to pin up to * FIXADDR_TOP. * - * For 32-bit the important bit is that we don't pin beyond there, - * because then we start getting into Xen's ptes. - * - * For 64-bit, we must skip the Xen hole in the middle of the address - * space, just after the big x86-64 virtual hole. + * We must skip the Xen hole in the middle of the address space, just after + * the big x86-64 virtual hole. */ static int __xen_pgd_walk(struct mm_struct *mm, pgd_t *pgd, int (*func)(struct mm_struct *mm, struct page *, @@ -654,14 +615,12 @@ static int __xen_pgd_walk(struct mm_struct *mm, pgd_t *pgd, limit--; BUG_ON(limit >= FIXADDR_TOP); -#ifdef CONFIG_X86_64 /* * 64-bit has a great big hole in the middle of the address * space, which contains the Xen mappings. */ hole_low = pgd_index(GUARD_HOLE_BASE_ADDR); hole_high = pgd_index(GUARD_HOLE_END_ADDR); -#endif nr = pgd_index(limit) + 1; for (i = 0; i < nr; i++) { @@ -787,6 +746,8 @@ static int xen_pin_page(struct mm_struct *mm, struct page *page, read-only, and can be pinned. */ static void __xen_pgd_pin(struct mm_struct *mm, pgd_t *pgd) { + pgd_t *user_pgd = xen_get_user_pgd(pgd); + trace_xen_mmu_pgd_pin(mm, pgd); xen_mc_batch(); @@ -800,26 +761,14 @@ static void __xen_pgd_pin(struct mm_struct *mm, pgd_t *pgd) xen_mc_batch(); } -#ifdef CONFIG_X86_64 - { - pgd_t *user_pgd = xen_get_user_pgd(pgd); + xen_do_pin(MMUEXT_PIN_L4_TABLE, PFN_DOWN(__pa(pgd))); - xen_do_pin(MMUEXT_PIN_L4_TABLE, PFN_DOWN(__pa(pgd))); - - if (user_pgd) { - xen_pin_page(mm, virt_to_page(user_pgd), PT_PGD); - xen_do_pin(MMUEXT_PIN_L4_TABLE, - PFN_DOWN(__pa(user_pgd))); - } + if (user_pgd) { + xen_pin_page(mm, virt_to_page(user_pgd), PT_PGD); + xen_do_pin(MMUEXT_PIN_L4_TABLE, + PFN_DOWN(__pa(user_pgd))); } -#else /* CONFIG_X86_32 */ -#ifdef CONFIG_X86_PAE - /* Need to make sure unshared kernel PMD is pinnable */ - xen_pin_page(mm, pgd_page(pgd[pgd_index(TASK_SIZE)]), - PT_PMD); -#endif - xen_do_pin(MMUEXT_PIN_L3_TABLE, PFN_DOWN(__pa(pgd))); -#endif /* CONFIG_X86_64 */ + xen_mc_issue(0); } @@ -870,9 +819,7 @@ static int __init xen_mark_pinned(struct mm_struct *mm, struct page *page, static void __init xen_after_bootmem(void) { static_branch_enable(&xen_struct_pages_ready); -#ifdef CONFIG_X86_64 SetPagePinned(virt_to_page(level3_user_vsyscall)); -#endif xen_pgd_walk(&init_mm, xen_mark_pinned, FIXADDR_TOP); } @@ -919,29 +866,19 @@ static int xen_unpin_page(struct mm_struct *mm, struct page *page, /* Release a pagetables pages back as normal RW */ static void __xen_pgd_unpin(struct mm_struct *mm, pgd_t *pgd) { + pgd_t *user_pgd = xen_get_user_pgd(pgd); + trace_xen_mmu_pgd_unpin(mm, pgd); xen_mc_batch(); xen_do_pin(MMUEXT_UNPIN_TABLE, PFN_DOWN(__pa(pgd))); -#ifdef CONFIG_X86_64 - { - pgd_t *user_pgd = xen_get_user_pgd(pgd); - - if (user_pgd) { - xen_do_pin(MMUEXT_UNPIN_TABLE, - PFN_DOWN(__pa(user_pgd))); - xen_unpin_page(mm, virt_to_page(user_pgd), PT_PGD); - } + if (user_pgd) { + xen_do_pin(MMUEXT_UNPIN_TABLE, + PFN_DOWN(__pa(user_pgd))); + xen_unpin_page(mm, virt_to_page(user_pgd), PT_PGD); } -#endif - -#ifdef CONFIG_X86_PAE - /* Need to make sure unshared kernel PMD is unpinned */ - xen_unpin_page(mm, pgd_page(pgd[pgd_index(TASK_SIZE)]), - PT_PMD); -#endif __xen_pgd_walk(mm, pgd, xen_unpin_page, USER_LIMIT); @@ -1089,7 +1026,6 @@ static void __init pin_pagetable_pfn(unsigned cmd, unsigned long pfn) BUG(); } -#ifdef CONFIG_X86_64 static void __init xen_cleanhighmap(unsigned long vaddr, unsigned long vaddr_end) { @@ -1273,17 +1209,15 @@ static void __init xen_pagetable_cleanhighmap(void) xen_cleanhighmap(addr, roundup(addr + size, PMD_SIZE * 2)); xen_start_info->pt_base = (unsigned long)__va(__pa(xen_start_info->pt_base)); } -#endif static void __init xen_pagetable_p2m_setup(void) { xen_vmalloc_p2m_tree(); -#ifdef CONFIG_X86_64 xen_pagetable_p2m_free(); xen_pagetable_cleanhighmap(); -#endif + /* And revector! Bye bye old array */ xen_start_info->mfn_list = (unsigned long)xen_p2m_addr; } @@ -1420,6 +1354,8 @@ static void __xen_write_cr3(bool kernel, unsigned long cr3) } static void xen_write_cr3(unsigned long cr3) { + pgd_t *user_pgd = xen_get_user_pgd(__va(cr3)); + BUG_ON(preemptible()); xen_mc_batch(); /* disables interrupts */ @@ -1430,20 +1366,14 @@ static void xen_write_cr3(unsigned long cr3) __xen_write_cr3(true, cr3); -#ifdef CONFIG_X86_64 - { - pgd_t *user_pgd = xen_get_user_pgd(__va(cr3)); - if (user_pgd) - __xen_write_cr3(false, __pa(user_pgd)); - else - __xen_write_cr3(false, 0); - } -#endif + if (user_pgd) + __xen_write_cr3(false, __pa(user_pgd)); + else + __xen_write_cr3(false, 0); xen_mc_issue(PARAVIRT_LAZY_CPU); /* interrupts restored */ } -#ifdef CONFIG_X86_64 /* * At the start of the day - when Xen launches a guest, it has already * built pagetables for the guest. We diligently look over them @@ -1478,49 +1408,39 @@ static void __init xen_write_cr3_init(unsigned long cr3) xen_mc_issue(PARAVIRT_LAZY_CPU); /* interrupts restored */ } -#endif static int xen_pgd_alloc(struct mm_struct *mm) { pgd_t *pgd = mm->pgd; - int ret = 0; + struct page *page = virt_to_page(pgd); + pgd_t *user_pgd; + int ret = -ENOMEM; BUG_ON(PagePinned(virt_to_page(pgd))); + BUG_ON(page->private != 0); -#ifdef CONFIG_X86_64 - { - struct page *page = virt_to_page(pgd); - pgd_t *user_pgd; - - BUG_ON(page->private != 0); - - ret = -ENOMEM; - - user_pgd = (pgd_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO); - page->private = (unsigned long)user_pgd; + user_pgd = (pgd_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO); + page->private = (unsigned long)user_pgd; - if (user_pgd != NULL) { + if (user_pgd != NULL) { #ifdef CONFIG_X86_VSYSCALL_EMULATION - user_pgd[pgd_index(VSYSCALL_ADDR)] = - __pgd(__pa(level3_user_vsyscall) | _PAGE_TABLE); + user_pgd[pgd_index(VSYSCALL_ADDR)] = + __pgd(__pa(level3_user_vsyscall) | _PAGE_TABLE); #endif - ret = 0; - } - - BUG_ON(PagePinned(virt_to_page(xen_get_user_pgd(pgd)))); + ret = 0; } -#endif + + BUG_ON(PagePinned(virt_to_page(xen_get_user_pgd(pgd)))); + return ret; } static void xen_pgd_free(struct mm_struct *mm, pgd_t *pgd) { -#ifdef CONFIG_X86_64 pgd_t *user_pgd = xen_get_user_pgd(pgd); if (user_pgd) free_page((unsigned long)user_pgd); -#endif } /* @@ -1539,7 +1459,6 @@ static void xen_pgd_free(struct mm_struct *mm, pgd_t *pgd) */ __visible pte_t xen_make_pte_init(pteval_t pte) { -#ifdef CONFIG_X86_64 unsigned long pfn; /* @@ -1553,7 +1472,7 @@ __visible pte_t xen_make_pte_init(pteval_t pte) pfn >= xen_start_info->first_p2m_pfn && pfn < xen_start_info->first_p2m_pfn + xen_start_info->nr_p2m_frames) pte &= ~_PAGE_RW; -#endif + pte = pte_pfn_to_mfn(pte); return native_make_pte(pte); } @@ -1561,13 +1480,6 @@ PV_CALLEE_SAVE_REGS_THUNK(xen_make_pte_init); static void __init xen_set_pte_init(pte_t *ptep, pte_t pte) { -#ifdef CONFIG_X86_32 - /* If there's an existing pte, then don't allow _PAGE_RW to be set */ - if (pte_mfn(pte) != INVALID_P2M_ENTRY - && pte_val_ma(*ptep) & _PAGE_PRESENT) - pte = __pte_ma(((pte_val_ma(*ptep) & _PAGE_RW) | ~_PAGE_RW) & - pte_val_ma(pte)); -#endif __xen_set_pte(ptep, pte); } @@ -1702,7 +1614,6 @@ static void xen_release_pmd(unsigned long pfn) xen_release_ptpage(pfn, PT_PMD); } -#ifdef CONFIG_X86_64 static void xen_alloc_pud(struct mm_struct *mm, unsigned long pfn) { xen_alloc_ptpage(mm, pfn, PT_PUD); @@ -1712,19 +1623,9 @@ static void xen_release_pud(unsigned long pfn) { xen_release_ptpage(pfn, PT_PUD); } -#endif void __init xen_reserve_top(void) { -#ifdef CONFIG_X86_32 - unsigned long top = HYPERVISOR_VIRT_START; - struct xen_platform_parameters pp; - - if (HYPERVISOR_xen_version(XENVER_platform_parameters, &pp) == 0) - top = pp.virt_start; - - reserve_top_address(-top); -#endif /* CONFIG_X86_32 */ } /* @@ -1733,11 +1634,7 @@ void __init xen_reserve_top(void) */ static void * __init __ka(phys_addr_t paddr) { -#ifdef CONFIG_X86_64 return (void *)(paddr + __START_KERNEL_map); -#else - return __va(paddr); -#endif } /* Convert a machine address to physical address */ @@ -1771,56 +1668,7 @@ static void __init set_page_prot(void *addr, pgprot_t prot) { return set_page_prot_flags(addr, prot, UVMF_NONE); } -#ifdef CONFIG_X86_32 -static void __init xen_map_identity_early(pmd_t *pmd, unsigned long max_pfn) -{ - unsigned pmdidx, pteidx; - unsigned ident_pte; - unsigned long pfn; - - level1_ident_pgt = extend_brk(sizeof(pte_t) * LEVEL1_IDENT_ENTRIES, - PAGE_SIZE); - ident_pte = 0; - pfn = 0; - for (pmdidx = 0; pmdidx < PTRS_PER_PMD && pfn < max_pfn; pmdidx++) { - pte_t *pte_page; - - /* Reuse or allocate a page of ptes */ - if (pmd_present(pmd[pmdidx])) - pte_page = m2v(pmd[pmdidx].pmd); - else { - /* Check for free pte pages */ - if (ident_pte == LEVEL1_IDENT_ENTRIES) - break; - - pte_page = &level1_ident_pgt[ident_pte]; - ident_pte += PTRS_PER_PTE; - - pmd[pmdidx] = __pmd(__pa(pte_page) | _PAGE_TABLE); - } - - /* Install mappings */ - for (pteidx = 0; pteidx < PTRS_PER_PTE; pteidx++, pfn++) { - pte_t pte; - - if (pfn > max_pfn_mapped) - max_pfn_mapped = pfn; - - if (!pte_none(pte_page[pteidx])) - continue; - - pte = pfn_pte(pfn, PAGE_KERNEL_EXEC); - pte_page[pteidx] = pte; - } - } - - for (pteidx = 0; pteidx < ident_pte; pteidx += PTRS_PER_PTE) - set_page_prot(&level1_ident_pgt[pteidx], PAGE_KERNEL_RO); - - set_page_prot(pmd, PAGE_KERNEL_RO); -} -#endif void __init xen_setup_machphys_mapping(void) { struct xen_machphys_mapping mapping; @@ -1831,13 +1679,8 @@ void __init xen_setup_machphys_mapping(void) } else { machine_to_phys_nr = MACH2PHYS_NR_ENTRIES; } -#ifdef CONFIG_X86_32 - WARN_ON((machine_to_phys_mapping + (machine_to_phys_nr - 1)) - < machine_to_phys_mapping); -#endif } -#ifdef CONFIG_X86_64 static void __init convert_pfn_mfn(void *v) { pte_t *pte = v; @@ -2168,105 +2011,6 @@ void __init xen_relocate_p2m(void) xen_start_info->nr_p2m_frames = n_frames; } -#else /* !CONFIG_X86_64 */ -static RESERVE_BRK_ARRAY(pmd_t, initial_kernel_pmd, PTRS_PER_PMD); -static RESERVE_BRK_ARRAY(pmd_t, swapper_kernel_pmd, PTRS_PER_PMD); -RESERVE_BRK(fixup_kernel_pmd, PAGE_SIZE); -RESERVE_BRK(fixup_kernel_pte, PAGE_SIZE); - -static void __init xen_write_cr3_init(unsigned long cr3) -{ - unsigned long pfn = PFN_DOWN(__pa(swapper_pg_dir)); - - BUG_ON(read_cr3_pa() != __pa(initial_page_table)); - BUG_ON(cr3 != __pa(swapper_pg_dir)); - - /* - * We are switching to swapper_pg_dir for the first time (from - * initial_page_table) and therefore need to mark that page - * read-only and then pin it. - * - * Xen disallows sharing of kernel PMDs for PAE - * guests. Therefore we must copy the kernel PMD from - * initial_page_table into a new kernel PMD to be used in - * swapper_pg_dir. - */ - swapper_kernel_pmd = - extend_brk(sizeof(pmd_t) * PTRS_PER_PMD, PAGE_SIZE); - copy_page(swapper_kernel_pmd, initial_kernel_pmd); - swapper_pg_dir[KERNEL_PGD_BOUNDARY] = - __pgd(__pa(swapper_kernel_pmd) | _PAGE_PRESENT); - set_page_prot(swapper_kernel_pmd, PAGE_KERNEL_RO); - - set_page_prot(swapper_pg_dir, PAGE_KERNEL_RO); - xen_write_cr3(cr3); - pin_pagetable_pfn(MMUEXT_PIN_L3_TABLE, pfn); - - pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, - PFN_DOWN(__pa(initial_page_table))); - set_page_prot(initial_page_table, PAGE_KERNEL); - set_page_prot(initial_kernel_pmd, PAGE_KERNEL); - - pv_ops.mmu.write_cr3 = &xen_write_cr3; -} - -/* - * For 32 bit domains xen_start_info->pt_base is the pgd address which might be - * not the first page table in the page table pool. - * Iterate through the initial page tables to find the real page table base. - */ -static phys_addr_t __init xen_find_pt_base(pmd_t *pmd) -{ - phys_addr_t pt_base, paddr; - unsigned pmdidx; - - pt_base = min(__pa(xen_start_info->pt_base), __pa(pmd)); - - for (pmdidx = 0; pmdidx < PTRS_PER_PMD; pmdidx++) - if (pmd_present(pmd[pmdidx]) && !pmd_large(pmd[pmdidx])) { - paddr = m2p(pmd[pmdidx].pmd); - pt_base = min(pt_base, paddr); - } - - return pt_base; -} - -void __init xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn) -{ - pmd_t *kernel_pmd; - - kernel_pmd = m2v(pgd[KERNEL_PGD_BOUNDARY].pgd); - - xen_pt_base = xen_find_pt_base(kernel_pmd); - xen_pt_size = xen_start_info->nr_pt_frames * PAGE_SIZE; - - initial_kernel_pmd = - extend_brk(sizeof(pmd_t) * PTRS_PER_PMD, PAGE_SIZE); - - max_pfn_mapped = PFN_DOWN(xen_pt_base + xen_pt_size + 512 * 1024); - - copy_page(initial_kernel_pmd, kernel_pmd); - - xen_map_identity_early(initial_kernel_pmd, max_pfn); - - copy_page(initial_page_table, pgd); - initial_page_table[KERNEL_PGD_BOUNDARY] = - __pgd(__pa(initial_kernel_pmd) | _PAGE_PRESENT); - - set_page_prot(initial_kernel_pmd, PAGE_KERNEL_RO); - set_page_prot(initial_page_table, PAGE_KERNEL_RO); - set_page_prot(empty_zero_page, PAGE_KERNEL_RO); - - pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, PFN_DOWN(__pa(pgd))); - - pin_pagetable_pfn(MMUEXT_PIN_L3_TABLE, - PFN_DOWN(__pa(initial_page_table))); - xen_write_cr3(__pa(initial_page_table)); - - memblock_reserve(xen_pt_base, xen_pt_size); -} -#endif /* CONFIG_X86_64 */ - void __init xen_reserve_special_pages(void) { phys_addr_t paddr; @@ -2300,12 +2044,7 @@ static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot) switch (idx) { case FIX_BTMAP_END ... FIX_BTMAP_BEGIN: -#ifdef CONFIG_X86_32 - case FIX_WP_TEST: -# ifdef CONFIG_HIGHMEM - case FIX_KMAP_BEGIN ... FIX_KMAP_END: -# endif -#elif defined(CONFIG_X86_VSYSCALL_EMULATION) +#ifdef CONFIG_X86_VSYSCALL_EMULATION case VSYSCALL_PAGE: #endif /* All local page mappings */ @@ -2357,9 +2096,7 @@ static void __init xen_post_allocator_init(void) pv_ops.mmu.set_pte = xen_set_pte; pv_ops.mmu.set_pmd = xen_set_pmd; pv_ops.mmu.set_pud = xen_set_pud; -#ifdef CONFIG_X86_64 pv_ops.mmu.set_p4d = xen_set_p4d; -#endif /* This will work as long as patching hasn't happened yet (which it hasn't) */ @@ -2367,15 +2104,11 @@ static void __init xen_post_allocator_init(void) pv_ops.mmu.alloc_pmd = xen_alloc_pmd; pv_ops.mmu.release_pte = xen_release_pte; pv_ops.mmu.release_pmd = xen_release_pmd; -#ifdef CONFIG_X86_64 pv_ops.mmu.alloc_pud = xen_alloc_pud; pv_ops.mmu.release_pud = xen_release_pud; -#endif pv_ops.mmu.make_pte = PV_CALLEE_SAVE(xen_make_pte); -#ifdef CONFIG_X86_64 pv_ops.mmu.write_cr3 = &xen_write_cr3; -#endif } static void xen_leave_lazy_mmu(void) @@ -2420,17 +2153,11 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = { .make_pte = PV_CALLEE_SAVE(xen_make_pte_init), .make_pgd = PV_CALLEE_SAVE(xen_make_pgd), -#ifdef CONFIG_X86_PAE - .set_pte_atomic = xen_set_pte_atomic, - .pte_clear = xen_pte_clear, - .pmd_clear = xen_pmd_clear, -#endif /* CONFIG_X86_PAE */ .set_pud = xen_set_pud_hyper, .make_pmd = PV_CALLEE_SAVE(xen_make_pmd), .pmd_val = PV_CALLEE_SAVE(xen_pmd_val), -#ifdef CONFIG_X86_64 .pud_val = PV_CALLEE_SAVE(xen_pud_val), .make_pud = PV_CALLEE_SAVE(xen_make_pud), .set_p4d = xen_set_p4d_hyper, @@ -2442,7 +2169,6 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = { .p4d_val = PV_CALLEE_SAVE(xen_p4d_val), .make_p4d = PV_CALLEE_SAVE(xen_make_p4d), #endif -#endif /* CONFIG_X86_64 */ .activate_mm = xen_activate_mm, .dup_mmap = xen_dup_mmap, diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c index 0acba2c712ab..be4151f42611 100644 --- a/arch/x86/xen/p2m.c +++ b/arch/x86/xen/p2m.c @@ -379,12 +379,8 @@ static void __init xen_rebuild_p2m_list(unsigned long *p2m) if (type == P2M_TYPE_PFN || i < chunk) { /* Use initial p2m page contents. */ -#ifdef CONFIG_X86_64 mfns = alloc_p2m_page(); copy_page(mfns, xen_p2m_addr + pfn); -#else - mfns = xen_p2m_addr + pfn; -#endif ptep = populate_extra_pte((unsigned long)(p2m + pfn)); set_pte(ptep, pfn_pte(PFN_DOWN(__pa(mfns)), PAGE_KERNEL)); @@ -467,7 +463,7 @@ EXPORT_SYMBOL_GPL(get_phys_to_machine); * Allocate new pmd(s). It is checked whether the old pmd is still in place. * If not, nothing is changed. This is okay as the only reason for allocating * a new pmd is to replace p2m_missing_pte or p2m_identity_pte by a individual - * pmd. In case of PAE/x86-32 there are multiple pmds to allocate! + * pmd. */ static pte_t *alloc_p2m_pmd(unsigned long addr, pte_t *pte_pg) { diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c index 3566e37241d7..7eab14d56369 100644 --- a/arch/x86/xen/setup.c +++ b/arch/x86/xen/setup.c @@ -32,7 +32,6 @@ #include #include #include "xen-ops.h" -#include "vdso.h" #include "mmu.h" #define GB(x) ((uint64_t)(x) * 1024 * 1024 * 1024) @@ -545,13 +544,10 @@ static unsigned long __init xen_get_pages_limit(void) { unsigned long limit; -#ifdef CONFIG_X86_32 - limit = GB(64) / PAGE_SIZE; -#else limit = MAXMEM / PAGE_SIZE; if (!xen_initial_domain() && xen_512gb_limit) limit = GB(512) / PAGE_SIZE; -#endif + return limit; } @@ -722,17 +718,8 @@ static void __init xen_reserve_xen_mfnlist(void) if (!xen_is_e820_reserved(start, size)) return; -#ifdef CONFIG_X86_32 - /* - * Relocating the p2m on 32 bit system to an arbitrary virtual address - * is not supported, so just give up. - */ - xen_raw_console_write("Xen hypervisor allocated p2m list conflicts with E820 map\n"); - BUG(); -#else xen_relocate_p2m(); memblock_free(start, size); -#endif } /** @@ -921,20 +908,6 @@ char * __init xen_memory_setup(void) return "Xen"; } -/* - * Set the bit indicating "nosegneg" library variants should be used. - * We only need to bother in pure 32-bit mode; compat 32-bit processes - * can have un-truncated segments, so wrapping around is allowed. - */ -static void __init fiddle_vdso(void) -{ -#ifdef CONFIG_X86_32 - u32 *mask = vdso_image_32.data + - vdso_image_32.sym_VDSO32_NOTE_MASK; - *mask |= 1 << VDSO_NOTE_NONEGSEG_BIT; -#endif -} - static int register_callback(unsigned type, const void *func) { struct callback_register callback = { @@ -951,11 +924,7 @@ void xen_enable_sysenter(void) int ret; unsigned sysenter_feature; -#ifdef CONFIG_X86_32 - sysenter_feature = X86_FEATURE_SEP; -#else sysenter_feature = X86_FEATURE_SYSENTER32; -#endif if (!boot_cpu_has(sysenter_feature)) return; @@ -967,7 +936,6 @@ void xen_enable_sysenter(void) void xen_enable_syscall(void) { -#ifdef CONFIG_X86_64 int ret; ret = register_callback(CALLBACKTYPE_syscall, xen_syscall_target); @@ -983,7 +951,6 @@ void xen_enable_syscall(void) if (ret != 0) setup_clear_cpu_cap(X86_FEATURE_SYSCALL32); } -#endif /* CONFIG_X86_64 */ } static void __init xen_pvmmu_arch_setup(void) @@ -1024,7 +991,6 @@ void __init xen_arch_setup(void) disable_cpuidle(); disable_cpufreq(); WARN_ON(xen_set_default_idle()); - fiddle_vdso(); #ifdef CONFIG_NUMA numa_off = 1; #endif diff --git a/arch/x86/xen/smp_pv.c b/arch/x86/xen/smp_pv.c index 9ea598dcc132..3a70cb1e9550 100644 --- a/arch/x86/xen/smp_pv.c +++ b/arch/x86/xen/smp_pv.c @@ -210,15 +210,6 @@ static void __init xen_pv_smp_prepare_boot_cpu(void) * sure the old memory can be recycled. */ make_lowmem_page_readwrite(xen_initial_gdt); -#ifdef CONFIG_X86_32 - /* - * Xen starts us with XEN_FLAT_RING1_DS, but linux code - * expects __USER_DS - */ - loadsegment(ds, __USER_DS); - loadsegment(es, __USER_DS); -#endif - xen_filter_cpu_maps(); xen_setup_vcpu_info_placement(); @@ -299,10 +290,6 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle) gdt = get_cpu_gdt_rw(cpu); -#ifdef CONFIG_X86_32 - ctxt->user_regs.fs = __KERNEL_PERCPU; - ctxt->user_regs.gs = __KERNEL_STACK_CANARY; -#endif memset(&ctxt->fpu_ctxt, 0, sizeof(ctxt->fpu_ctxt)); /* @@ -340,12 +327,7 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle) ctxt->kernel_ss = __KERNEL_DS; ctxt->kernel_sp = task_top_of_stack(idle); -#ifdef CONFIG_X86_32 - ctxt->event_callback_cs = __KERNEL_CS; - ctxt->failsafe_callback_cs = __KERNEL_CS; -#else ctxt->gs_base_kernel = per_cpu_offset(cpu); -#endif ctxt->event_callback_eip = (unsigned long)xen_asm_exc_xen_hypervisor_callback; ctxt->failsafe_callback_eip = diff --git a/arch/x86/xen/vdso.h b/arch/x86/xen/vdso.h deleted file mode 100644 index 873c54c488fe..000000000000 --- a/arch/x86/xen/vdso.h +++ /dev/null @@ -1,6 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ - -/* Bit used for the pseudo-hwcap for non-negative segments. We use - bit 1 to avoid bugs in some versions of glibc when bit 0 is - used; the choice is otherwise arbitrary. */ -#define VDSO_NOTE_NONEGSEG_BIT 1 diff --git a/arch/x86/xen/xen-asm.S b/arch/x86/xen/xen-asm.S index 508fe204520b..c59d077510bf 100644 --- a/arch/x86/xen/xen-asm.S +++ b/arch/x86/xen/xen-asm.S @@ -76,11 +76,7 @@ SYM_FUNC_END(xen_save_fl_direct) */ SYM_FUNC_START(xen_restore_fl_direct) FRAME_BEGIN -#ifdef CONFIG_X86_64 testw $X86_EFLAGS_IF, %di -#else - testb $X86_EFLAGS_IF>>8, %ah -#endif setz PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_mask /* * Preempt here doesn't matter because that will deal with any @@ -104,15 +100,6 @@ SYM_FUNC_END(xen_restore_fl_direct) */ SYM_FUNC_START(check_events) FRAME_BEGIN -#ifdef CONFIG_X86_32 - push %eax - push %ecx - push %edx - call xen_force_evtchn_callback - pop %edx - pop %ecx - pop %eax -#else push %rax push %rcx push %rdx @@ -132,7 +119,6 @@ SYM_FUNC_START(check_events) pop %rdx pop %rcx pop %rax -#endif FRAME_END ret SYM_FUNC_END(check_events) diff --git a/arch/x86/xen/xen-asm_32.S b/arch/x86/xen/xen-asm_32.S deleted file mode 100644 index 4757cec33abe..000000000000 --- a/arch/x86/xen/xen-asm_32.S +++ /dev/null @@ -1,185 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -/* - * Asm versions of Xen pv-ops, suitable for direct use. - * - * We only bother with direct forms (ie, vcpu in pda) of the - * operations here; the indirect forms are better handled in C. - */ - -#include -#include -#include -#include - -#include - -#include - -/* Pseudo-flag used for virtual NMI, which we don't implement yet */ -#define XEN_EFLAGS_NMI 0x80000000 - -/* - * This is run where a normal iret would be run, with the same stack setup: - * 8: eflags - * 4: cs - * esp-> 0: eip - * - * This attempts to make sure that any pending events are dealt with - * on return to usermode, but there is a small window in which an - * event can happen just before entering usermode. If the nested - * interrupt ends up setting one of the TIF_WORK_MASK pending work - * flags, they will not be tested again before returning to - * usermode. This means that a process can end up with pending work, - * which will be unprocessed until the process enters and leaves the - * kernel again, which could be an unbounded amount of time. This - * means that a pending signal or reschedule event could be - * indefinitely delayed. - * - * The fix is to notice a nested interrupt in the critical window, and - * if one occurs, then fold the nested interrupt into the current - * interrupt stack frame, and re-process it iteratively rather than - * recursively. This means that it will exit via the normal path, and - * all pending work will be dealt with appropriately. - * - * Because the nested interrupt handler needs to deal with the current - * stack state in whatever form its in, we keep things simple by only - * using a single register which is pushed/popped on the stack. - */ - -.macro POP_FS -1: - popw %fs -.pushsection .fixup, "ax" -2: movw $0, (%esp) - jmp 1b -.popsection - _ASM_EXTABLE(1b,2b) -.endm - -SYM_CODE_START(xen_iret) - /* test eflags for special cases */ - testl $(X86_EFLAGS_VM | XEN_EFLAGS_NMI), 8(%esp) - jnz hyper_iret - - push %eax - ESP_OFFSET=4 # bytes pushed onto stack - - /* Store vcpu_info pointer for easy access */ -#ifdef CONFIG_SMP - pushw %fs - movl $(__KERNEL_PERCPU), %eax - movl %eax, %fs - movl %fs:xen_vcpu, %eax - POP_FS -#else - movl %ss:xen_vcpu, %eax -#endif - - /* check IF state we're restoring */ - testb $X86_EFLAGS_IF>>8, 8+1+ESP_OFFSET(%esp) - - /* - * Maybe enable events. Once this happens we could get a - * recursive event, so the critical region starts immediately - * afterwards. However, if that happens we don't end up - * resuming the code, so we don't have to be worried about - * being preempted to another CPU. - */ - setz %ss:XEN_vcpu_info_mask(%eax) -xen_iret_start_crit: - - /* check for unmasked and pending */ - cmpw $0x0001, %ss:XEN_vcpu_info_pending(%eax) - - /* - * If there's something pending, mask events again so we can - * jump back into exc_xen_hypervisor_callback. Otherwise do not - * touch XEN_vcpu_info_mask. - */ - jne 1f - movb $1, %ss:XEN_vcpu_info_mask(%eax) - -1: popl %eax - - /* - * From this point on the registers are restored and the stack - * updated, so we don't need to worry about it if we're - * preempted - */ -iret_restore_end: - - /* - * Jump to hypervisor_callback after fixing up the stack. - * Events are masked, so jumping out of the critical region is - * OK. - */ - je xen_asm_exc_xen_hypervisor_callback - -1: iret -xen_iret_end_crit: - _ASM_EXTABLE(1b, asm_iret_error) - -hyper_iret: - /* put this out of line since its very rarely used */ - jmp hypercall_page + __HYPERVISOR_iret * 32 -SYM_CODE_END(xen_iret) - - .globl xen_iret_start_crit, xen_iret_end_crit - -/* - * This is called by xen_asm_exc_xen_hypervisor_callback in entry_32.S when it sees - * that the EIP at the time of interrupt was between - * xen_iret_start_crit and xen_iret_end_crit. - * - * The stack format at this point is: - * ---------------- - * ss : (ss/esp may be present if we came from usermode) - * esp : - * eflags } outer exception info - * cs } - * eip } - * ---------------- - * eax : outer eax if it hasn't been restored - * ---------------- - * eflags } - * cs } nested exception info - * eip } - * return address : (into xen_asm_exc_xen_hypervisor_callback) - * - * In order to deliver the nested exception properly, we need to discard the - * nested exception frame such that when we handle the exception, we do it - * in the context of the outer exception rather than starting a new one. - * - * The only caveat is that if the outer eax hasn't been restored yet (i.e. - * it's still on stack), we need to restore its value here. -*/ -.pushsection .noinstr.text, "ax" -SYM_CODE_START(xen_iret_crit_fixup) - /* - * Paranoia: Make sure we're really coming from kernel space. - * One could imagine a case where userspace jumps into the - * critical range address, but just before the CPU delivers a - * PF, it decides to deliver an interrupt instead. Unlikely? - * Definitely. Easy to avoid? Yes. - */ - testb $2, 2*4(%esp) /* nested CS */ - jnz 2f - - /* - * If eip is before iret_restore_end then stack - * hasn't been restored yet. - */ - cmpl $iret_restore_end, 1*4(%esp) - jae 1f - - movl 4*4(%esp), %eax /* load outer EAX */ - ret $4*4 /* discard nested EIP, CS, and EFLAGS as - * well as the just restored EAX */ - -1: - ret $3*4 /* discard nested EIP, CS, and EFLAGS */ - -2: - ret -SYM_CODE_END(xen_iret_crit_fixup) -.popsection diff --git a/arch/x86/xen/xen-head.S b/arch/x86/xen/xen-head.S index 1ba601df3a37..2d7c8f34f56c 100644 --- a/arch/x86/xen/xen-head.S +++ b/arch/x86/xen/xen-head.S @@ -35,13 +35,8 @@ SYM_CODE_START(startup_xen) rep __ASM_SIZE(stos) mov %_ASM_SI, xen_start_info -#ifdef CONFIG_X86_64 mov initial_stack(%rip), %rsp -#else - mov initial_stack, %esp -#endif -#ifdef CONFIG_X86_64 /* Set up %gs. * * The base of %gs always points to fixed_percpu_data. If the @@ -53,7 +48,6 @@ SYM_CODE_START(startup_xen) movq $INIT_PER_CPU_VAR(fixed_percpu_data),%rax cdq wrmsr -#endif call xen_start_kernel SYM_CODE_END(startup_xen) diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig index 1d339ef92422..ea6c1e7e3e42 100644 --- a/drivers/xen/Kconfig +++ b/drivers/xen/Kconfig @@ -52,9 +52,7 @@ config XEN_BALLOON_MEMORY_HOTPLUG config XEN_BALLOON_MEMORY_HOTPLUG_LIMIT int "Hotplugged memory limit (in GiB) for a PV guest" - default 512 if X86_64 - default 4 if X86_32 - range 0 64 if X86_32 + default 512 depends on XEN_HAVE_PVMMU depends on XEN_BALLOON_MEMORY_HOTPLUG help