[RFC PATCH 3/3] iommu/vt-d: Show region type in arch_rmrr_sanity_check()

Aaron Tomlin
2022-06-11T20:49:16Z

This patch will attempt to describe the region type in the event
that a given RMRR entry is not within a reserved region.

Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
---
arch/x86/include/asm/iommu.h | 9 ++++++---
arch/x86/kernel/e820.c | 5 +++--
2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/arch/x86/include/asm/iommu.h b/arch/x86/include/asm/iommu.h
index bf1ed2ddc74b..d21366644520 100644
--- a/arch/x86/include/asm/iommu.h
+++ b/arch/x86/include/asm/iommu.h
@@ -17,12 +17,15 @@ arch_rmrr_sanity_check(struct acpi_dmar_reserved_memory *rmrr)
{
u64 start = rmrr->base_address;
u64 end = rmrr->end_address + 1;
+ struct e820_entry *entry;

- if (e820__mapped_all(start, end, E820_TYPE_RESERVED))
+ entry = __e820__mapped_all(start, end, 0);
+
+ if (entry && entry->type == E820_TYPE_RESERVED)
return 0;

- pr_err(FW_BUG "No firmware reserved region can cover this RMRR [%#018Lx-%#018Lx], contact BIOS vendor for fixes\n",
- start, end - 1);
+ pr_err(FW_BUG "No firmware reserved region can cover this RMRR [%s: %#018Lx-%#018Lx], contact BIOS vendor for fixes\n",
+ e820_type_to_string(entry), start, end - 1);
return -EINVAL;
}

diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index 95b994cf80cd..165e9a444bb9 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -1073,7 +1073,7 @@ void __init e820__finish_early_params(void)

const char *__init e820_type_to_string(struct e820_entry *entry)
{
- switch (entry->type) {
+ switch (entry && entry->type) {
case E820_TYPE_RESERVED_KERN: /* Fall-through: */
case E820_TYPE_RAM: return "System RAM";
case E820_TYPE_ACPI: return "ACPI Tables";
@@ -1083,8 +1083,9 @@ const char *__init e820_type_to_string(struct e820_entry *entry)
case E820_TYPE_PMEM: return "Persistent Memory";
case E820_TYPE_RESERVED: return "Reserved";
case E820_TYPE_SOFT_RESERVED: return "Soft Reserved";
- default: return "Unknown E820 type";
+ default: break;
}
+ return "Unknown E820 type";
}

static unsigned long __init e820_type_to_iomem_type(struct e820_entry *entry)
--
2.34.1