x86: Cleanup highmap after brk is concluded
Now cleanup_highmap actually is in two steps: one is early in head64.c
and only clears above _end; a second one is in init_memory_mapping() and
tries to clean from _brk_end to _end.
It should check if those boundaries are PMD_SIZE aligned but currently
does not.
Also init_memory_mapping() is called several times for numa or memory
hotplug, so we really should not handle initial kernel mappings there.
This patch moves cleanup_highmap() down after _brk_end is settled so
we can do everything in one step.
Also we honor max_pfn_mapped in the implementation of cleanup_highmap.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
LKML-Reference: <alpine.DEB.2.00.1103171739050.3382@kaball-desktop>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index b176f2b..4a52a5f 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -294,30 +294,11 @@
else
direct_gbpages = 0;
}
-
-static void __init cleanup_highmap_brk_end(void)
-{
- pud_t *pud;
- pmd_t *pmd;
-
- mmu_cr4_features = read_cr4();
-
- /*
- * _brk_end cannot change anymore, but it and _end may be
- * located on different 2M pages. cleanup_highmap(), however,
- * can only consider _end when it runs, so destroy any
- * mappings beyond _brk_end here.
- */
- pud = pud_offset(pgd_offset_k(_brk_end), _brk_end);
- pmd = pmd_offset(pud, _brk_end - 1);
- while (++pmd <= pmd_offset(pud, (unsigned long)_end - 1))
- pmd_clear(pmd);
-}
#else
static inline void init_gbpages(void)
{
}
-static inline void cleanup_highmap_brk_end(void)
+static void __init cleanup_highmap(void)
{
}
#endif
@@ -330,8 +311,6 @@
/* Mark brk area as locked down and no longer taking any
new allocations */
_brk_start = 0;
-
- cleanup_highmap_brk_end();
}
#ifdef CONFIG_BLK_DEV_INITRD
@@ -950,6 +929,8 @@
*/
reserve_brk();
+ cleanup_highmap();
+
memblock.current_limit = get_max_mapped();
memblock_x86_fill();