Stefano Stabellini
2013-Apr-29 17:04 UTC
[PATCH] xen/arm: move the tlb_flush in create_p2m_entries to the end of the function
Move the flush after the pagetable entry has actually been written to
avoid races with other vcpus refreshing the same entriy.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
xen/arch/arm/p2m.c | 9 +++++----
1 files changed, 5 insertions(+), 4 deletions(-)
diff --git a/xen/arch/arm/p2m.c b/xen/arch/arm/p2m.c
index 1e8c8b4..9fc5534 100644
--- a/xen/arch/arm/p2m.c
+++ b/xen/arch/arm/p2m.c
@@ -133,7 +133,7 @@ static int create_p2m_entries(struct domain *d,
paddr_t maddr,
int mattr)
{
- int rc;
+ int rc, flush;
struct p2m_domain *p2m = &d->arch.p2m;
lpae_t *first = NULL, *second = NULL, *third = NULL;
paddr_t addr;
@@ -186,10 +186,8 @@ static int create_p2m_entries(struct domain *d,
third =
map_domain_page(second[second_table_offset(addr)].p2m.base);
cur_second_offset = second_table_offset(addr);
}
- /* else: third already valid */
- if ( third[third_table_offset(addr)].p2m.valid )
- flush_tlb_all_local();
+ flush = third[third_table_offset(addr)].p2m.valid;
/* Allocate a new RAM page and attach */
switch (op) {
@@ -226,6 +224,9 @@ static int create_p2m_entries(struct domain *d,
}
break;
}
+
+ if ( flush )
+ flush_tlb_all_local();
}
rc = 0;
--
1.7.2.5
Ian Campbell
2013-Apr-30 10:58 UTC
Re: [PATCH] xen/arm: move the tlb_flush in create_p2m_entries to the end of the function
On Mon, 2013-04-29 at 18:04 +0100, Stefano Stabellini wrote:> Move the flush after the pagetable entry has actually been written to > avoid races with other vcpus refreshing the same entriy. > > Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>Acked + applied.