Commit 5f871994 authored by Juergen Gross's avatar Juergen Gross Committed by Ingo Molnar
Browse files

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: be35d91c ("xen: tolerate ACPI NVS memory overlapping with Xen allocated memory")
Signed-off-by: default avatarJuergen Gross <jgross@suse.com>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Cc: xen-devel@lists.xenproject.org
Link: https://patch.msgid.link/20260505080653.197775-1-jgross@suse.com
parent 7fd2df20

arch/x86/xen/setup.c

+9 −4
Original line number Diff line number Diff line
@@ -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++;

	}

}