From 5dc64a3442b98eaa0e3730c35fcf00cf962a93e7 Mon Sep 17 00:00:00 2001 From: Ian Campbell Date: Fri, 10 Oct 2008 11:27:38 +0100 Subject: [PATCH] xen: do not reserve 2 pages of padding between hypervisor and fixmap. When reserving space for the hypervisor the Xen paravirt backend adds an extra two pages (this was carried forward from the 2.6.18-xen tree which had them "for safety"). Depending on various CONFIG options this can cause the boot time fixmaps to span multiple PMDs which is not supported and triggers a WARN in early_ioremap_init(). This was exposed by 2216d199b1430d1c0affb1498a9ebdbd9c0de439 which moved the dmi table parsing earlier. x86: fix CONFIG_X86_RESERVE_LOW_64K=y The bad_bios_dmi_table() quirk never triggered because we do DMI setup too late. Move it a bit earlier. There is no real reason to reserve these two extra pages and the fixmap already incorporates FIX_HOLE which serves the same purpose. None of the other callers of reserve_top_address do this. Signed-off-by: Ian Campbell Signed-off-by: Ingo Molnar --- arch/x86/xen/enlighten.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 85692c9f6496..977a54255fb4 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -1370,7 +1370,7 @@ static void __init xen_reserve_top(void) if (HYPERVISOR_xen_version(XENVER_platform_parameters, &pp) == 0) top = pp.virt_start; - reserve_top_address(-top + 2 * PAGE_SIZE); + reserve_top_address(-top); #endif /* CONFIG_X86_32 */ } -- 2.30.2