lkml.org 
[lkml]   [2012]   [May]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[34-longterm 078/179] xen: partially revert "xen: set max_pfn_mapped to the last pfn mapped"
Date
From: Stefano Stabellini <stefano.stabellini@eu.citrix.com>

-------------------
This is a commit scheduled for the next v2.6.34 longterm release.
http://git.kernel.org/?p=linux/kernel/git/paulg/longterm-queue-2.6.34.git
If you see a problem with using this for longterm, please comment.
-------------------
commit a91d92875ee94e4703fd017ccaadb48cfb344994 upstream.

We only need to set max_pfn_mapped to the last pfn mapped on x86_64 to
make sure that cleanup_highmap doesn't remove important mappings at
_end.

We don't need to do this on x86_32 because cleanup_highmap is not called
on x86_32. Besides lowering max_pfn_mapped on x86_32 has the unwanted
side effect of limiting the amount of memory available for the 1:1
kernel pagetable allocation.

This patch reverts the x86_32 part of the original patch.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
---
arch/x86/xen/mmu.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index 4916176..96cdf78 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -1641,6 +1641,11 @@ static __init void xen_map_identity_early(pmd_t *pmd, unsigned long max_pfn)
for (pteidx = 0; pteidx < PTRS_PER_PTE; pteidx++, pfn++) {
pte_t pte;

+#ifdef CONFIG_X86_32
+ if (pfn > max_pfn_mapped)
+ max_pfn_mapped = pfn;
+#endif
+
if (!pte_none(pte_page[pteidx]))
continue;

@@ -1753,7 +1758,9 @@ __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd,
{
pmd_t *kernel_pmd;

- max_pfn_mapped = PFN_DOWN(__pa(xen_start_info->mfn_list));
+ max_pfn_mapped = PFN_DOWN(__pa(xen_start_info->pt_base) +
+ xen_start_info->nr_pt_frames * PAGE_SIZE +
+ 512*1024);

kernel_pmd = m2v(pgd[KERNEL_PGD_BOUNDARY].pgd);
memcpy(level2_kernel_pgt, kernel_pmd, sizeof(pmd_t) * PTRS_PER_PMD);
--
1.7.9.6


\
 
 \ /
  Last update: 2012-05-15 06:22    [from the cache]
©2003-2011 Jasper Spaans