x86/paravirt: remove lazy mode in interrupts
Impact: simplification, robustness
Make paravirt_lazy_mode() always return PARAVIRT_LAZY_NONE
when in an interrupt. This prevents interrupt code from
accidentally inheriting an outer lazy state, and instead
does everything synchronously. Outer batched operations
are left deferred.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index a03b727..cfbb4a73 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -225,12 +225,10 @@
if (!pmd_present(*pmd_k))
return NULL;
- if (!pmd_present(*pmd)) {
+ if (!pmd_present(*pmd))
set_pmd(pmd, *pmd_k);
- arch_flush_lazy_mmu_mode();
- } else {
+ else
BUG_ON(pmd_page(*pmd) != pmd_page(*pmd_k));
- }
return pmd_k;
}
diff --git a/arch/x86/mm/highmem_32.c b/arch/x86/mm/highmem_32.c
index 00f127c..e81dfa4 100644
--- a/arch/x86/mm/highmem_32.c
+++ b/arch/x86/mm/highmem_32.c
@@ -87,7 +87,6 @@
vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
BUG_ON(!pte_none(*(kmap_pte-idx)));
set_pte(kmap_pte-idx, mk_pte(page, prot));
- arch_flush_lazy_mmu_mode();
return (void *)vaddr;
}
@@ -117,7 +116,6 @@
#endif
}
- arch_flush_lazy_mmu_mode();
pagefault_enable();
}
diff --git a/arch/x86/mm/iomap_32.c b/arch/x86/mm/iomap_32.c
index 04102d4..b6a61f3 100644
--- a/arch/x86/mm/iomap_32.c
+++ b/arch/x86/mm/iomap_32.c
@@ -74,7 +74,6 @@
if (vaddr == __fix_to_virt(FIX_KMAP_BEGIN+idx))
kpte_clear_flush(kmap_pte-idx, vaddr);
- arch_flush_lazy_mmu_mode();
pagefault_enable();
}
EXPORT_SYMBOL_GPL(iounmap_atomic);
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 9c42949..9015e5e 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -824,13 +824,6 @@
vm_unmap_aliases();
- /*
- * If we're called with lazy mmu updates enabled, the
- * in-memory pte state may be stale. Flush pending updates to
- * bring them up to date.
- */
- arch_flush_lazy_mmu_mode();
-
cpa.vaddr = addr;
cpa.numpages = numpages;
cpa.mask_set = mask_set;
@@ -873,13 +866,6 @@
} else
cpa_flush_all(cache);
- /*
- * If we've been called with lazy mmu updates enabled, then
- * make sure that everything gets flushed out before we
- * return.
- */
- arch_flush_lazy_mmu_mode();
-
out:
return ret;
}