Re: [tip regression] efi: Allow drivers to reserve boot services forever == toxic

From: Mike Galbraith
Date: Sun Sep 18 2016 - 02:09:45 EST


On Sat, 2016-09-17 at 20:58 +0100, Matt Fleming wrote:

> These addresses are pretty low. Can you try the hacky patch plus
> Ricardo's change in commit 3dad6f7f6975 ("x86/efi: Defer efi_esrt_init
> until after memblock_x86_fill"). He fixed a bug where it's possible to
> run out of memblock regions.

---
arch/x86/platform/efi/quirks.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)

--- a/arch/x86/platform/efi/quirks.c
+++ b/arch/x86/platform/efi/quirks.c
@@ -201,8 +201,12 @@ void __init efi_arch_mem_reserve(phys_ad
return;
}

+//XXX size += addr % EFI_PAGE_SIZE;
+//MATT size = round_up(size, EFI_PAGE_SIZE);
+//XXX addr = round_down(addr, EFI_PAGE_SIZE);
+
mr.range.start = addr;
- mr.range.end = addr + size;
+ mr.range.end = addr + size;//MATT - 1;
mr.attribute = md.attribute | EFI_MEMORY_RUNTIME;

num_entries = efi_memmap_split_count(&md, &mr.range);
@@ -225,7 +229,12 @@ void __init efi_arch_mem_reserve(phys_ad
efi_memmap_insert(&efi.memmap, new, &mr);
early_memunmap(new, new_size);

+#if 0
efi_memmap_install(new_phys, num_entries);
+#endif
+ printk(KERN_DEBUG "MIKE md.phys_addr:0x%Lx md.virt_addr:0x%Lx md.num_pages:%Ld\n", md.phys_addr, md.virt_addr, md.num_pages);
+ printk(KERN_DEBUG "MIKE mr.range.start:0x%Lx mr.range.end:0x%Lx\n", mr.range.start, mr.range.end);
+ printk(KERN_DEBUG "MIKE efi_memmap_install(0x%Lx, %d);\n", new_phys, num_entries);
}

/*

tip v4.8-rc6-654-g0d941b5745e4

virgin
[ 0.000000] MIKE md.phys_addr:0xded81000 md.virt_addr:0x0 md.num_pages:520
[ 0.000000] MIKE mr.range.start:0xdef87998 mr.range.end:0xdef879d0
[ 0.000000] MIKE efi_memmap_install(0x9d640, 51);

+MATT changes
[ 0.000000] MIKE md.phys_addr:0xded81000 md.virt_addr:0x0 md.num_pages:520
[ 0.000000] MIKE mr.range.start:0xdef87998 mr.range.end:0xdef88997
[ 0.000000] MIKE efi_memmap_install(0x9d600, 53);

+MATT changes + XXX changes (boots/works without #if 0)
[ 0.000000] MIKE md.phys_addr:0xded81000 md.virt_addr:0x0 md.num_pages:520
[ 0.000000] MIKE mr.range.start:0xdef87000 mr.range.end:0xdef87fff
[ 0.000000] MIKE efi_memmap_install(0x9d640, 51);