From fc38151947477596aa27df6c4306ad6008dc6711 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Tue, 16 Sep 2008 10:07:34 +0200 Subject: x86: add X86_RESERVE_LOW_64K This bugzilla: http://bugzilla.kernel.org/show_bug.cgi?id=11237 Documents a wide range of systems where the BIOS utilizes the first 64K of physical memory during suspend/resume and other hardware events. Currently we reserve this memory on all AMI and Phoenix BIOS systems. Life is too short to hunt subtle memory corruption problems like this, so we try to be robust by default. Still, allow this to be overriden: allow users who want that first 64K of memory to be available to the kernel disable the quirk, via CONFIG_X86_RESERVE_LOW_64K=n. Also, allow the early reservation to overlap with other early reservations. Signed-off-by: Ingo Molnar --- arch/x86/kernel/setup.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'arch/x86/kernel/setup.c') diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 3371954..786c188 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -735,13 +735,14 @@ static int __init dmi_low_memory_corruption(const struct dmi_system_id *d) "%s detected: BIOS may corrupt low RAM, working it around.\n", d->ident); - reserve_early(0x0, 0x10000, "BIOS quirk"); + reserve_early_overlap_ok(0x0, 0x10000, "BIOS quirk"); return 0; } /* List of systems that have known low memory corruption BIOS problems */ static struct dmi_system_id __initdata bad_bios_dmi_table[] = { +#ifdef CONFIG_X86_RESERVE_LOW_64K { .callback = dmi_low_memory_corruption, .ident = "AMI BIOS", @@ -757,6 +758,7 @@ static struct dmi_system_id __initdata bad_bios_dmi_table[] = { }, }, {} +#endif }; /* -- cgit v1.1