From: David Vrabel <[email protected]> In xen_memory_setup(), if a page that is being released has a VA mapping this must also be updated. Otherwise, the page will be not released completely -- it will still be referenced in Xen and won't be freed util the mapping is removed and this prevents it from being reallocated at a different PFN.
This was already being done for the ISA memory region in xen_ident_map_ISA() but on many systems this was omitting a few pages as many systems marked a few pages below the ISA memory region as reserved in the e820 map. This fixes errors such as: (XEN) page_alloc.c:1148:d0 Over-allocation for domain 0: 2097153 > 2097152 (XEN) memory.c:133:d0 Could not allocate order=0 extent: id=0 memflags=0 (0 of 17) Signed-off-by: David Vrabel <[email protected]> Signed-off-by: Konrad Rzeszutek Wilk <[email protected]> (cherry picked from commit 83d51ab473dddde7df858015070ed22b84ebe9a9) Signed-off-by: Daniel Kiper <[email protected]> Tested-by: Daniel Kiper <[email protected]> Tested-by: Konrad Rzeszutek Wilk <[email protected]> --- arch/x86/xen/enlighten.c | 1 - arch/x86/xen/mmu.c | 23 ----------------------- arch/x86/xen/setup.c | 41 ++++++++++++++++++++++++++++++++++------- arch/x86/xen/xen-ops.h | 1 - 4 files changed, 34 insertions(+), 32 deletions(-) diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 9598038..d0825fb 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -1390,7 +1390,6 @@ asmlinkage void __init xen_start_kernel(void) xen_raw_console_write("mapping kernel into physical memory\n"); pgd = xen_setup_kernel_pagetable(pgd, xen_start_info->nr_pages); - xen_ident_map_ISA(); /* Allocate and initialize top and mid mfn levels for p2m structure */ xen_build_mfn_list_list(); diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index cf7fe36..6b5a93a 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -1953,29 +1953,6 @@ static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot) #endif } -void __init xen_ident_map_ISA(void) -{ - unsigned long pa; - - /* - * If we're dom0, then linear map the ISA machine addresses into - * the kernel's address space. - */ - if (!xen_initial_domain()) - return; - - xen_raw_printk("Xen: setup ISA identity maps\n"); - - for (pa = ISA_START_ADDRESS; pa < ISA_END_ADDRESS; pa += PAGE_SIZE) { - pte_t pte = mfn_pte(PFN_DOWN(pa), PAGE_KERNEL_IO); - - if (HYPERVISOR_update_va_mapping(PAGE_OFFSET + pa, pte, 0)) - BUG(); - } - - xen_flush_tlb(); -} - static void __init xen_post_allocator_init(void) { pv_mmu_ops.set_pte = xen_set_pte; diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c index 282e807..24d2522 100644 --- a/arch/x86/xen/setup.c +++ b/arch/x86/xen/setup.c @@ -147,6 +147,13 @@ static unsigned long __init xen_do_chunk(unsigned long start, return len; } + +static unsigned long __init xen_release_chunk(unsigned long start, + unsigned long end) +{ + return xen_do_chunk(start, end, true); +} + static unsigned long __init xen_populate_chunk( const struct e820entry *list, size_t map_size, unsigned long max_pfn, unsigned long *last_pfn, @@ -205,6 +212,29 @@ static unsigned long __init xen_populate_chunk( } return done; } + +static void __init xen_set_identity_and_release_chunk( + unsigned long start_pfn, unsigned long end_pfn, unsigned long nr_pages, + unsigned long *released, unsigned long *identity) +{ + unsigned long pfn; + + /* + * If the PFNs are currently mapped, the VA mapping also needs + * to be updated to be 1:1. + */ + for (pfn = start_pfn; pfn <= max_pfn_mapped && pfn < end_pfn; pfn++) + (void)HYPERVISOR_update_va_mapping( + (unsigned long)__va(pfn << PAGE_SHIFT), + mfn_pte(pfn, PAGE_KERNEL_IO), 0); + + if (start_pfn < nr_pages) + *released += xen_release_chunk( + start_pfn, min(end_pfn, nr_pages)); + + *identity += set_phys_range_identity(start_pfn, end_pfn); +} + static unsigned long __init xen_set_identity_and_release( const struct e820entry *list, size_t map_size, unsigned long nr_pages) { @@ -234,14 +264,11 @@ static unsigned long __init xen_set_identity_and_release( if (entry->type == E820_RAM) end_pfn = PFN_UP(entry->addr); - if (start_pfn < end_pfn) { - if (start_pfn < nr_pages) - released += xen_do_chunk( - start_pfn, min(end_pfn, nr_pages), true); + if (start_pfn < end_pfn) + xen_set_identity_and_release_chunk( + start_pfn, end_pfn, nr_pages, + &released, &identity); - identity += set_phys_range_identity( - start_pfn, end_pfn); - } start = end; } } diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h index b095739..506fa08 100644 --- a/arch/x86/xen/xen-ops.h +++ b/arch/x86/xen/xen-ops.h @@ -28,7 +28,6 @@ void xen_setup_shared_info(void); void xen_build_mfn_list_list(void); void xen_setup_machphys_mapping(void); pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn); -void xen_ident_map_ISA(void); void xen_reserve_top(void); extern unsigned long xen_max_p2m_pfn; -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
