From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> When remove_e820_regions() clips a resource because an E820 region overlaps it, log a note in dmesg to add in debugging. Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> --- arch/x86/kernel/resource.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/x86/kernel/resource.c b/arch/x86/kernel/resource.c index 8ffe68437744..30d524adb012 100644 --- a/arch/x86/kernel/resource.c +++ b/arch/x86/kernel/resource.c @@ -1,5 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 #include <linux/ioport.h> +#include <linux/printk.h> #include <asm/e820/api.h> static void resource_clip(struct resource *res, resource_size_t start, @@ -28,6 +29,7 @@ static void remove_e820_regions(struct resource *avail) int i; struct e820_entry *entry; u64 e820_start, e820_end; + struct resource orig = *avail; for (i = 0; i < e820_table->nr_entries; i++) { entry = &e820_table->entries[i]; @@ -35,6 +37,11 @@ static void remove_e820_regions(struct resource *avail) e820_end = entry->addr + entry->size - 1; resource_clip(avail, e820_start, e820_end); + if (orig.start != avail->start || orig.end != avail->end) { + pr_info("clipped %pR to %pR for e820 entry [mem %#010Lx-%#010Lx]\n", + &orig, avail, e820_start, e820_end); + orig = *avail; + } } } -- 2.25.1