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| author | Juergen Gross <jgross@suse.com> | 2018-08-20 17:24:20 +0200 |
|---|---|---|
| committer | Boris Ostrovsky <boris.ostrovsky@oracle.com> | 2018-08-20 14:46:26 -0400 |
| commit | 75f2d3a0cef5cd8cd41772c9f8ada37dee9c9369 (patch) | |
| tree | 89b3a7fa08753ecdf14490cf955152af3fe7d78f /arch/x86 | |
| parent | 00f53f758d9baffef9dc3efedf534bb0dc1872eb (diff) | |
| download | linux-75f2d3a0cef5cd8cd41772c9f8ada37dee9c9369.tar.gz | |
x86/xen: enable early use of set_fixmap in 32-bit Xen PV guest
Commit 7b25b9cb0dad83 ("x86/xen/time: Initialize pv xen time in
init_hypervisor_platform()") moved the mapping of the shared info area
before pagetable_init(). This breaks booting as 32-bit PV guest as the
use of set_fixmap isn't possible at this time on 32-bit.
This can be worked around by populating the needed PMD on 32-bit
kernel earlier.
In order not to reimplement populate_extra_pte() using extend_brk()
for allocating new page tables extend alloc_low_pages() to do that in
case the early page table pool is not yet available.
Fixes: 7b25b9cb0dad83 ("x86/xen/time: Initialize pv xen time in init_hypervisor_platform()")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/mm/init.c | 17 | ||||
| -rw-r--r-- | arch/x86/xen/enlighten_pv.c | 2 | ||||
| -rw-r--r-- | arch/x86/xen/mmu_pv.c | 2 |
3 files changed, 16 insertions, 5 deletions
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index acfab322fbe0..5c32a7665492 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -99,15 +99,22 @@ __ref void *alloc_low_pages(unsigned int num) } if ((pgt_buf_end + num) > pgt_buf_top || !can_use_brk_pgt) { - unsigned long ret; - if (min_pfn_mapped >= max_pfn_mapped) - panic("alloc_low_pages: ran out of memory"); - ret = memblock_find_in_range(min_pfn_mapped << PAGE_SHIFT, + unsigned long ret = 0; + + if (min_pfn_mapped < max_pfn_mapped) { + ret = memblock_find_in_range( + min_pfn_mapped << PAGE_SHIFT, max_pfn_mapped << PAGE_SHIFT, PAGE_SIZE * num , PAGE_SIZE); + } + if (ret) + memblock_reserve(ret, PAGE_SIZE * num); + else if (can_use_brk_pgt) + ret = __pa(extend_brk(PAGE_SIZE * num, PAGE_SIZE)); + if (!ret) panic("alloc_low_pages: can not alloc memory"); - memblock_reserve(ret, PAGE_SIZE * num); + pfn = ret >> PAGE_SHIFT; } else { pfn = pgt_buf_end; diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c index a26a11d8d0eb..52a7c3faee0c 100644 --- a/arch/x86/xen/enlighten_pv.c +++ b/arch/x86/xen/enlighten_pv.c @@ -122,6 +122,8 @@ static void __init xen_banner(void) static void __init xen_pv_init_platform(void) { + populate_extra_pte(fix_to_virt(FIX_PARAVIRT_BOOTMAP)); + set_fixmap(FIX_PARAVIRT_BOOTMAP, xen_start_info->shared_info); HYPERVISOR_shared_info = (void *)fix_to_virt(FIX_PARAVIRT_BOOTMAP); diff --git a/arch/x86/xen/mmu_pv.c b/arch/x86/xen/mmu_pv.c index 52206ad81e4b..9e7012858420 100644 --- a/arch/x86/xen/mmu_pv.c +++ b/arch/x86/xen/mmu_pv.c @@ -2171,6 +2171,8 @@ void __init xen_relocate_p2m(void) #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) { |