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由 Lianbo Jiang 提交于
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: NLianbo Jiang <lijiang@redhat.com> Signed-off-by: NBorislav Petkov <bp@suse.de> Reviewed-by: NTom 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
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