x86/kexec: Add the ACPI NVS region to the ident map

mainline inclusion
from mainline-5a949b38839e undefined
commit 5a949b38839e
category: bugfix
bugzilla: 17337
CVE: NA

-------------------------------------------------

With the recent addition of RSDP parsing in the decompression stage,
a kexec-ed kernel now needs ACPI tables to be covered by the identity
mapping. And in commit

  6bbeb276b71f ("x86/kexec: Add the EFI system tables and ACPI tables to the ident map")

the ACPI tables memory region was added to the ident map.

But some machines have only an ACPI NVS memory region and the ACPI
tables are located in that region. In such case, the kexec-ed kernel
will still fail when trying to access ACPI tables if they're not mapped.

So add the NVS memory region to the ident map as well.

 [ bp: Massage. ]

Fixes: 6bbeb276b71f ("x86/kexec: Add the EFI system tables and ACPI tables to the ident map")
Suggested-by: NJunichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: NKairui Song <kasong@redhat.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Tested-by: NJunichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Chao Fan <fanc.fnst@cn.fujitsu.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: kexec@lists.infradead.org
Cc: Lianbo Jiang <lijiang@redhat.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190610073617.19767-1-kasong@redhat.comSigned-off-by: NChen Zhou <chenzhou10@huawei.com>
Reviewed-by: NXiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

arch/x86/kernel/machine_kexec_64.c

@@ -54,14 +54,26 @@ static int mem_region_callback(struct resource *res, void *arg)
 static int
 map_acpi_tables(struct x86_mapping_info *info, pgd_t *level4p)
 {
-	unsigned long flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 	struct init_pgtable_data data;
+	unsigned long flags;
+	int ret;
 
 	data.info = info;
 	data.level4p = level4p;
 	flags = IORESOURCE_MEM | IORESOURCE_BUSY;
-	return walk_iomem_res_desc(IORES_DESC_ACPI_TABLES, flags, 0, -1,
-				   &data, mem_region_callback);
+
+	ret = walk_iomem_res_desc(IORES_DESC_ACPI_TABLES, flags, 0, -1,
+				  &data, mem_region_callback);
+	if (ret && ret != -EINVAL)
+		return ret;
+
+	/* ACPI tables could be located in ACPI Non-volatile Storage region */
+	ret = walk_iomem_res_desc(IORES_DESC_ACPI_NV_STORAGE, flags, 0, -1,
+				  &data, mem_region_callback);
+	if (ret && ret != -EINVAL)
+		return ret;
+
+	return 0;
 }
 #else
 static int map_acpi_tables(struct x86_mapping_info *info, pgd_t *level4p) { return 0; }