Mailing List Archive

commit 9487a6d62af1edb0bd497b546839b4a0cd768603
Author: Julien Grall <jgrall@amazon.com>
AuthorDate: Thu Dec 15 11:44:45 2022 +0000
Commit: Julien Grall <jgrall@amazon.com>
CommitDate: Thu Dec 15 11:46:37 2022 +0000

xen/arm: Enable use of dump_pt_walk() early during boot

At the moment, dump_pt_walk() is using map_domain_page() to map
the page tables.

map_domain_page() is only usuable after init_domheap_mappings() is called
(arm32) or the xenheap has been initialized (arm64).

This means it can be hard to diagnose incorrect page-tables during
early boot. So update dump_pt_walk() to xen_{, un}map_table() instead.

Note that the two helpers are moved earlier to avoid forward declaring
them.

Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
---
xen/arch/arm/mm.c | 56 +++++++++++++++++++++++++++----------------------------
1 file changed, 28 insertions(+), 28 deletions(-)

diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c
index 630175276f..1fd207b27c 100644
--- a/xen/arch/arm/mm.c
+++ b/xen/arch/arm/mm.c
@@ -177,6 +177,30 @@ static void __init __maybe_unused build_assertions(void)
#undef CHECK_SAME_SLOT
}

+static lpae_t *xen_map_table(mfn_t mfn)
+{
+ /*
+ * During early boot, map_domain_page() may be unusable. Use the
+ * PMAP to map temporarily a page-table.
+ */
+ if ( system_state == SYS_STATE_early_boot )
+ return pmap_map(mfn);
+
+ return map_domain_page(mfn);
+}
+
+static void xen_unmap_table(const lpae_t *table)
+{
+ /*
+ * During early boot, xen_map_table() will not use map_domain_page()
+ * but the PMAP.
+ */
+ if ( system_state == SYS_STATE_early_boot )
+ pmap_unmap(table);
+ else
+ unmap_domain_page(table);
+}
+
void dump_pt_walk(paddr_t ttbr, paddr_t addr,
unsigned int root_level,
unsigned int nr_root_tables)
@@ -216,7 +240,7 @@ void dump_pt_walk(paddr_t ttbr, paddr_t addr,
else
root_table = 0;

- mapping = map_domain_page(mfn_add(root_mfn, root_table));
+ mapping = xen_map_table(mfn_add(root_mfn, root_table));

for ( level = root_level; ; level++ )
{
@@ -232,11 +256,11 @@ void dump_pt_walk(paddr_t ttbr, paddr_t addr,
break;

/* For next iteration */
- unmap_domain_page(mapping);
- mapping = map_domain_page(lpae_get_mfn(pte));
+ xen_unmap_table(mapping);
+ mapping = xen_map_table(lpae_get_mfn(pte));
}

- unmap_domain_page(mapping);
+ xen_unmap_table(mapping);
}

void dump_hyp_walk(vaddr_t addr)
@@ -699,30 +723,6 @@ void *ioremap(paddr_t pa, size_t len)
return ioremap_attr(pa, len, PAGE_HYPERVISOR_NOCACHE);
}

-static lpae_t *xen_map_table(mfn_t mfn)
-{
- /*
- * During early boot, map_domain_page() may be unusable. Use the
- * PMAP to map temporarily a page-table.
- */
- if ( system_state == SYS_STATE_early_boot )
- return pmap_map(mfn);
-
- return map_domain_page(mfn);
-}
-
-static void xen_unmap_table(const lpae_t *table)
-{
- /*
- * During early boot, xen_map_table() will not use map_domain_page()
- * but the PMAP.
- */
- if ( system_state == SYS_STATE_early_boot )
- pmap_unmap(table);
- else
- unmap_domain_page(table);
-}
-
static int create_xen_table(lpae_t *entry)
{
mfn_t mfn;
--
generated by git-patchbot for /home/xen/git/xen.git#master