The following commit has been merged into the x86/urgent branch of tip:
Commit-ID: 5f8719945244dd65b5fa06195f4600db62581610
Gitweb: https://git.kernel.org/tip/5f8719945244dd65b5fa06195f4600db62581610
Author: Juergen Gross <jgross@suse.com>
AuthorDate: Tue, 05 May 2026 10:06:53 +02:00
Committer: Ingo Molnar <mingo@kernel.org>
CommitterDate: Tue, 05 May 2026 10:17:00 +02:00
x86/xen: Fix a potential problem in xen_e820_resolve_conflicts()
When fixing a conflict in xen_e820_resolve_conflicts(), the loop over
the E820 map entries needs to be restarted, as the E820 map will have
been modified by the fix. Otherwise entries might be skipped by
accident.
Fixes: be35d91c8880 ("xen: tolerate ACPI NVS memory overlapping with Xen allocated memory")
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: xen-devel@lists.xenproject.org
Link: https://patch.msgid.link/20260505080653.197775-1-jgross@suse.com
---
arch/x86/xen/setup.c | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)
diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index ac8021c..bb95a05 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -695,17 +695,22 @@ static void __init xen_e820_resolve_conflicts(phys_addr_t start,
return;
end = start + size;
- entry = xen_e820_table.entries;
+ mapcnt = 0;
- for (mapcnt = 0; mapcnt < xen_e820_table.nr_entries; mapcnt++) {
+ while (mapcnt < xen_e820_table.nr_entries) {
+ entry = xen_e820_table.entries + mapcnt;
if (entry->addr >= end)
return;
if (entry->addr + entry->size > start &&
- entry->type == E820_TYPE_NVS)
+ entry->type == E820_TYPE_NVS) {
xen_e820_swap_entry_with_ram(entry);
+ /* E820 map has been changed, restart loop! */
+ mapcnt = 0;
+ continue;
+ }
- entry++;
+ mapcnt++;
}
}