From ae9e13d621d6795ec1ad6bf10bd2549c6c3feca4 Mon Sep 17 00:00:00 2001 From: Lianbo Jiang Date: Tue, 23 Apr 2019 09:30:05 +0800 Subject: [PATCH] x86/e820, ioport: Add a new I/O resource descriptor IORES_DESC_RESERVED When executing the kexec_file_load() syscall, the first kernel needs to pass the e820 reserved ranges to the second kernel because some devices (PCI, for example) need them present in the kdump kernel for proper initialization. But the kernel can not exactly match the e820 reserved ranges when walking through the iomem resources using the default IORES_DESC_NONE descriptor, because there are several types of e820 ranges which are marked IORES_DESC_NONE, see e820_type_to_iores_desc(). Therefore, add a new I/O resource descriptor called IORES_DESC_RESERVED to mark exactly those ranges. It will be used to match the reserved resource ranges when walking through iomem resources. [ bp: Massage commit message. ] Suggested-by: Borislav Petkov Signed-off-by: Lianbo Jiang Signed-off-by: Borislav Petkov Cc: Andrew Morton Cc: Andy Lutomirski Cc: bhe@redhat.com Cc: dave.hansen@linux.intel.com Cc: dyoung@redhat.com Cc: "H. Peter Anvin" Cc: Huang Zijiang Cc: Ingo Molnar Cc: Joe Perches Cc: Juergen Gross Cc: kexec@lists.infradead.org Cc: Masayoshi Mizuma Cc: Michal Hocko Cc: Mike Rapoport Cc: Naoya Horiguchi Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Tom Lendacky Cc: x86-ml Link: https://lkml.kernel.org/r/20190423013007.17838-2-lijiang@redhat.com --- arch/x86/kernel/e820.c | 2 +- include/linux/ioport.h | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c index 8f32e705a980..e69408bf664b 100644 --- a/arch/x86/kernel/e820.c +++ b/arch/x86/kernel/e820.c @@ -1063,10 +1063,10 @@ static unsigned long __init e820_type_to_iores_desc(struct e820_entry *entry) case E820_TYPE_NVS: return IORES_DESC_ACPI_NV_STORAGE; case E820_TYPE_PMEM: return IORES_DESC_PERSISTENT_MEMORY; case E820_TYPE_PRAM: return IORES_DESC_PERSISTENT_MEMORY_LEGACY; + case E820_TYPE_RESERVED: return IORES_DESC_RESERVED; case E820_TYPE_RESERVED_KERN: /* Fall-through: */ case E820_TYPE_RAM: /* Fall-through: */ case E820_TYPE_UNUSABLE: /* Fall-through: */ - case E820_TYPE_RESERVED: /* Fall-through: */ default: return IORES_DESC_NONE; } } diff --git a/include/linux/ioport.h b/include/linux/ioport.h index da0ebaec25f0..6ed59de48bd5 100644 --- a/include/linux/ioport.h +++ b/include/linux/ioport.h @@ -133,6 +133,7 @@ enum { IORES_DESC_PERSISTENT_MEMORY_LEGACY = 5, IORES_DESC_DEVICE_PRIVATE_MEMORY = 6, IORES_DESC_DEVICE_PUBLIC_MEMORY = 7, + IORES_DESC_RESERVED = 8, }; /* helpers to define resources */ -- GitLab