From: Ard Biesheuvel Date: Wed, 13 Dec 2023 08:40:29 +0000 (+0100) Subject: arm64: ptdump: Discover start of vmemmap region at runtime X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=f9cca2444187f46e0bc90dfc3a5feb7154dbf38d;p=linux.git arm64: ptdump: Discover start of vmemmap region at runtime We will soon reclaim the part of the vmemmap region that covers VA space that is not addressable by the hardware. To avoid confusion, ensure that the 'vmemmap start' marker points at the start of the region that is actually being used for the struct page array, rather than the start of the region we set aside for it at build time. Signed-off-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20231213084024.2367360-13-ardb@google.com Signed-off-by: Catalin Marinas Acked-by: Mark Rutland --- diff --git a/arch/arm64/mm/ptdump.c b/arch/arm64/mm/ptdump.c index 66ccb8d6997e8..5f0849528ccf1 100644 --- a/arch/arm64/mm/ptdump.c +++ b/arch/arm64/mm/ptdump.c @@ -346,6 +346,8 @@ void ptdump_check_wx(void) static int __init ptdump_init(void) { + u64 page_offset = _PAGE_OFFSET(vabits_actual); + u64 vmemmap_start = (u64)virt_to_page((void *)page_offset); struct addr_marker m[] = { { PAGE_OFFSET, "Linear Mapping start" }, { PAGE_END, "Linear Mapping end" }, @@ -357,7 +359,7 @@ static int __init ptdump_init(void) { MODULES_END, "Modules end" }, { VMALLOC_START, "vmalloc() area" }, { VMALLOC_END, "vmalloc() end" }, - { VMEMMAP_START, "vmemmap start" }, + { vmemmap_start, "vmemmap start" }, { VMEMMAP_END, "vmemmap end" }, { PCI_IO_START, "PCI I/O start" }, { PCI_IO_END, "PCI I/O end" },