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authorLianbo Jiang <lijiang@redhat.com>2018-09-30 11:10:32 +0800
committerBorislav Petkov <bp@suse.de>2018-10-06 12:08:24 +0200
commit8780158cf977ea5f9912931a30b3d575b36dba22 (patch)
treef1ec4f6d18241336803ed720f22ee80cbdf6bd19 /drivers/iommu
parent9cf38d5559e813cccdba8b44c82cc46ba48d0896 (diff)
downloadlinux-8780158cf977ea5f9912931a30b3d575b36dba22.tar.bz2
iommu/amd: Remap the IOMMU device table with the memory encryption mask for kdump
The kdump kernel copies the IOMMU device table from the old device table which is encrypted when SME is enabled in the first kernel. So remap the old device table with the memory encryption mask in the kdump kernel. [ bp: Massage commit message. ] Signed-off-by: Lianbo Jiang <lijiang@redhat.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Acked-by: Joerg Roedel <jroedel@suse.de> Cc: kexec@lists.infradead.org Cc: tglx@linutronix.de Cc: mingo@redhat.com Cc: hpa@zytor.com Cc: akpm@linux-foundation.org Cc: dan.j.williams@intel.com Cc: bhelgaas@google.com Cc: baiyaowei@cmss.chinamobile.com Cc: tiwai@suse.de Cc: brijesh.singh@amd.com Cc: dyoung@redhat.com Cc: bhe@redhat.com Link: https://lkml.kernel.org/r/20180930031033.22110-4-lijiang@redhat.com
Diffstat (limited to 'drivers/iommu')
-rw-r--r--drivers/iommu/amd_iommu_init.c14
1 files changed, 12 insertions, 2 deletions
diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index 84b3e4445d46..3931c7de7c69 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -902,12 +902,22 @@ static bool copy_device_table(void)
}
}
- old_devtb_phys = entry & PAGE_MASK;
+ /*
+ * When SME is enabled in the first kernel, the entry includes the
+ * memory encryption mask(sme_me_mask), we must remove the memory
+ * encryption mask to obtain the true physical address in kdump kernel.
+ */
+ old_devtb_phys = __sme_clr(entry) & PAGE_MASK;
+
if (old_devtb_phys >= 0x100000000ULL) {
pr_err("The address of old device table is above 4G, not trustworthy!\n");
return false;
}
- old_devtb = memremap(old_devtb_phys, dev_table_size, MEMREMAP_WB);
+ old_devtb = (sme_active() && is_kdump_kernel())
+ ? (__force void *)ioremap_encrypted(old_devtb_phys,
+ dev_table_size)
+ : memremap(old_devtb_phys, dev_table_size, MEMREMAP_WB);
+
if (!old_devtb)
return false;