diff options
author | Lianbo Jiang <lijiang@redhat.com> | 2018-09-27 10:19:51 +0300 |
---|---|---|
committer | Borislav Petkov <bp@suse.de> | 2018-10-06 12:57:51 +0300 |
commit | c3a7a61c192ec350330128edb13db33a9bc0ace1 (patch) | |
tree | 1487bec52841498a78338aad0c6e6a70a5e9ae54 /arch/x86/include | |
parent | b3541fbc3c25bf2ba6d03a450c07f824e318f9b9 (diff) | |
download | linux-c3a7a61c192ec350330128edb13db33a9bc0ace1.tar.xz |
x86/ioremap: Add an ioremap_encrypted() helper
When SME is enabled, the memory is encrypted in the first kernel. In
this case, SME also needs to be enabled in the kdump kernel, and we have
to remap the old memory with the memory encryption mask.
The case of concern here is if SME is active in the first kernel,
and it is active too in the kdump kernel. There are four cases to be
considered:
a. dump vmcore
It is encrypted in the first kernel, and needs be read out in the
kdump kernel.
b. crash notes
When dumping vmcore, the people usually need to read useful
information from notes, and the notes is also encrypted.
c. iommu device table
It's encrypted in the first kernel, kdump kernel needs to access its
content to analyze and get information it needs.
d. mmio of AMD iommu
not encrypted in both kernels
Add a new bool parameter @encrypted to __ioremap_caller(). If set,
memory will be remapped with the SME mask.
Add a new function ioremap_encrypted() to explicitly pass in a true
value for @encrypted. Use ioremap_encrypted() for the above a, b, c
cases.
[ bp: cleanup commit message, extern defs in io.h and drop forgotten
include. ]
Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
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
Cc: jroedel@suse.de
Link: https://lkml.kernel.org/r/20180927071954.29615-2-lijiang@redhat.com
Diffstat (limited to 'arch/x86/include')
-rw-r--r-- | arch/x86/include/asm/io.h | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h index 6de64840dd22..6df53efcecfd 100644 --- a/arch/x86/include/asm/io.h +++ b/arch/x86/include/asm/io.h @@ -187,11 +187,12 @@ extern void __iomem *ioremap_nocache(resource_size_t offset, unsigned long size) #define ioremap_nocache ioremap_nocache extern void __iomem *ioremap_uc(resource_size_t offset, unsigned long size); #define ioremap_uc ioremap_uc - extern void __iomem *ioremap_cache(resource_size_t offset, unsigned long size); #define ioremap_cache ioremap_cache extern void __iomem *ioremap_prot(resource_size_t offset, unsigned long size, unsigned long prot_val); #define ioremap_prot ioremap_prot +extern void __iomem *ioremap_encrypted(resource_size_t phys_addr, unsigned long size); +#define ioremap_encrypted ioremap_encrypted /** * ioremap - map bus memory into CPU space |