From: kfraser@localhost.localdomain Date: Fri, 10 Nov 2006 17:35:09 +0000 (+0000) Subject: [LINUX] Support variable hypervisor_virt_start. X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~15551^2~25 X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=b63bf4c4820faa994cd81df5a7f58339c09d4c76;p=xen.git [LINUX] Support variable hypervisor_virt_start. Introduce a new elfnote that specifies the lower boundary the kernel wants to tolerate for the hypervisor hole. Signed-off-by: Jan Beulich --- diff --git a/linux-2.6-xen-sparse/arch/i386/kernel/head-xen.S b/linux-2.6-xen-sparse/arch/i386/kernel/head-xen.S index dcef669792..1d0278c69b 100644 --- a/linux-2.6-xen-sparse/arch/i386/kernel/head-xen.S +++ b/linux-2.6-xen-sparse/arch/i386/kernel/head-xen.S @@ -9,7 +9,7 @@ #include #include #include -#include +#include #include /* @@ -192,6 +192,7 @@ ENTRY(cpu_gdt_table) #endif /* !CONFIG_XEN_COMPAT_030002 */ ELFNOTE(Xen, XEN_ELFNOTE_ENTRY, .long, startup_32) ELFNOTE(Xen, XEN_ELFNOTE_HYPERCALL_PAGE, .long, hypercall_page) + ELFNOTE(Xen, XEN_ELFNOTE_HV_START_LOW, .long, HYPERVISOR_VIRT_START) ELFNOTE(Xen, XEN_ELFNOTE_FEATURES, .asciz, "writable_page_tables|writable_descriptor_tables|auto_translated_physmap|pae_pgdir_above_4gb|supervisor_mode_kernel") #ifdef CONFIG_X86_PAE ELFNOTE(Xen, XEN_ELFNOTE_PAE_MODE, .asciz, "yes") diff --git a/linux-2.6-xen-sparse/arch/i386/mm/fault-xen.c b/linux-2.6-xen-sparse/arch/i386/mm/fault-xen.c index 16a0155ecb..4939ab106e 100644 --- a/linux-2.6-xen-sparse/arch/i386/mm/fault-xen.c +++ b/linux-2.6-xen-sparse/arch/i386/mm/fault-xen.c @@ -282,12 +282,6 @@ static int spurious_fault(struct pt_regs *regs, pmd_t *pmd; pte_t *pte; -#ifdef CONFIG_XEN - /* Faults in hypervisor area are never spurious. */ - if (address >= HYPERVISOR_VIRT_START) - return 0; -#endif - /* Reserved-bit violation or user access to kernel space? */ if (error_code & 0x0c) return 0; @@ -372,7 +366,7 @@ fastcall void __kprobes do_page_fault(struct pt_regs *regs, if (unlikely(address >= TASK_SIZE)) { #ifdef CONFIG_XEN /* Faults in hypervisor area can never be patched up. */ - if (address >= HYPERVISOR_VIRT_START) + if (address >= hypervisor_virt_start) goto bad_area_nosemaphore; #endif if (!(error_code & 5)) diff --git a/linux-2.6-xen-sparse/arch/i386/mm/init-xen.c b/linux-2.6-xen-sparse/arch/i386/mm/init-xen.c index 4f0175462a..4d2b33068f 100644 --- a/linux-2.6-xen-sparse/arch/i386/mm/init-xen.c +++ b/linux-2.6-xen-sparse/arch/i386/mm/init-xen.c @@ -130,7 +130,7 @@ static void __init page_table_range_init (unsigned long start, unsigned long end pud = pud_offset(pgd, vaddr); pmd = pmd_offset(pud, vaddr); for (; (pmd_idx < PTRS_PER_PMD) && (vaddr != end); pmd++, pmd_idx++) { - if (vaddr < HYPERVISOR_VIRT_START && pmd_none(*pmd)) + if (vaddr < hypervisor_virt_start && pmd_none(*pmd)) one_page_table_init(pmd); vaddr += PMD_SIZE; @@ -187,7 +187,7 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base) pmd += pmd_idx; for (; pmd_idx < PTRS_PER_PMD && pfn < max_low_pfn; pmd++, pmd_idx++) { unsigned int address = pfn * PAGE_SIZE + PAGE_OFFSET; - if (address >= HYPERVISOR_VIRT_START) + if (address >= hypervisor_virt_start) continue; /* Map with big pages if possible, otherwise create normal page tables. */ @@ -410,7 +410,7 @@ static void __init pagetable_init (void) * created - mappings will be set by set_fixmap(): */ vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK; - page_table_range_init(vaddr, 0, pgd_base); + page_table_range_init(vaddr, hypervisor_virt_start, pgd_base); permanent_kmaps_init(pgd_base); } diff --git a/linux-2.6-xen-sparse/arch/i386/mm/pgtable-xen.c b/linux-2.6-xen-sparse/arch/i386/mm/pgtable-xen.c index 843c9d0fd3..d843538917 100644 --- a/linux-2.6-xen-sparse/arch/i386/mm/pgtable-xen.c +++ b/linux-2.6-xen-sparse/arch/i386/mm/pgtable-xen.c @@ -186,9 +186,16 @@ void set_pmd_pfn(unsigned long vaddr, unsigned long pfn, pgprot_t flags) } static int nr_fixmaps = 0; +unsigned long hypervisor_virt_start = HYPERVISOR_VIRT_START; unsigned long __FIXADDR_TOP = (HYPERVISOR_VIRT_START - 2 * PAGE_SIZE); EXPORT_SYMBOL(__FIXADDR_TOP); +void __init set_fixaddr_top() +{ + BUG_ON(nr_fixmaps > 0); + __FIXADDR_TOP = hypervisor_virt_start - 2 * PAGE_SIZE; +} + void __set_fixmap (enum fixed_addresses idx, maddr_t phys, pgprot_t flags) { unsigned long address = __fix_to_virt(idx); @@ -211,12 +218,6 @@ void __set_fixmap (enum fixed_addresses idx, maddr_t phys, pgprot_t flags) nr_fixmaps++; } -void set_fixaddr_top(unsigned long top) -{ - BUG_ON(nr_fixmaps > 0); - __FIXADDR_TOP = top - PAGE_SIZE; -} - pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address) { pte_t *pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO); diff --git a/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/fixmap.h b/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/fixmap.h index 992a7c13ed..a9c3cc28fd 100644 --- a/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/fixmap.h +++ b/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/fixmap.h @@ -98,7 +98,7 @@ enum fixed_addresses { extern void __set_fixmap(enum fixed_addresses idx, maddr_t phys, pgprot_t flags); -extern void set_fixaddr_top(unsigned long top); +extern void set_fixaddr_top(void); #define set_fixmap(idx, phys) \ __set_fixmap(idx, phys, PAGE_KERNEL) diff --git a/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/hypervisor.h b/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/hypervisor.h index a037eb24e4..ef82d35728 100644 --- a/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/hypervisor.h +++ b/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/hypervisor.h @@ -56,6 +56,10 @@ extern shared_info_t *HYPERVISOR_shared_info; +#ifdef CONFIG_X86_32 +extern unsigned long hypervisor_virt_start; +#endif + /* arch/xen/i386/kernel/setup.c */ extern start_info_t *xen_start_info; #ifdef CONFIG_XEN_PRIVILEGED_GUEST diff --git a/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/pgtable-2level-defs.h b/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/pgtable-2level-defs.h index 3791d2de39..bd6346f410 100644 --- a/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/pgtable-2level-defs.h +++ b/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/pgtable-2level-defs.h @@ -9,7 +9,6 @@ #define PGDIR_SHIFT 22 #define PTRS_PER_PGD 1024 -#define PTRS_PER_PGD_NO_HV (HYPERVISOR_VIRT_START >> PGDIR_SHIFT) /* * the i386 is two-level, so we don't really have any diff --git a/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/pgtable-3level-defs.h b/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/pgtable-3level-defs.h index 10445c142c..148c8d9e78 100644 --- a/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/pgtable-3level-defs.h +++ b/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/pgtable-3level-defs.h @@ -8,7 +8,6 @@ */ #define PGDIR_SHIFT 30 #define PTRS_PER_PGD 4 -#define PTRS_PER_PGD_NO_HV 4 /* * PMD_SHIFT determines the size of the area a middle-level diff --git a/linux-2.6-xen-sparse/include/asm-i386/mach-xen/setup_arch_post.h b/linux-2.6-xen-sparse/include/asm-i386/mach-xen/setup_arch_post.h index 7314dedbde..bed1e1d211 100644 --- a/linux-2.6-xen-sparse/include/asm-i386/mach-xen/setup_arch_post.h +++ b/linux-2.6-xen-sparse/include/asm-i386/mach-xen/setup_arch_post.h @@ -92,8 +92,10 @@ static void __init machine_specific_arch_setup(void) #endif if (HYPERVISOR_xen_version(XENVER_platform_parameters, - &pp) == 0) - set_fixaddr_top(pp.virt_start - PAGE_SIZE); + &pp) == 0) { + hypervisor_virt_start = pp.virt_start; + set_fixaddr_top(); + } machine_to_phys_mapping = (unsigned long *)MACH2PHYS_VIRT_START; machine_to_phys_nr_ents = MACH2PHYS_NR_ENTRIES; diff --git a/xen/include/public/elfnote.h b/xen/include/public/elfnote.h index 8f03504b1e..ccf959d6e1 100644 --- a/xen/include/public/elfnote.h +++ b/xen/include/public/elfnote.h @@ -138,6 +138,15 @@ */ #define XEN_ELFNOTE_BSD_SYMTAB 11 +/* + * The lowest address the hypervisor hole can begin at (numeric). + * + * This must not be set higher than HYPERVISOR_VIRT_START. Its presence + * also indicates to the hypervisor that the kernel can deal with the + * hole starting at a higher address. + */ +#define XEN_ELFNOTE_HV_START_LOW 12 + #endif /* __XEN_PUBLIC_ELFNOTE_H__ */ /*