From c19a5f35e315837170ee337eed21c7087ea94192 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Wed, 11 Jan 2017 15:49:04 +0100 Subject: [PATCH] x86/e820/32: Fix e820_search_gap() error handling on x86-32 GCC correctly points out that on 32-bit kernels, e820_search_gap() not finding a start now leads to pci_mem_start ('gapstart') being set to an uninitialized value: arch/x86/kernel/e820.c: In function 'e820_setup_gap': arch/x86/kernel/e820.c:641:16: error: 'gapstart' may be used uninitialized in this function [-Werror=maybe-uninitialized] This restores the behavior from before this cleanup: b4ed1d15b453 ("x86/e820: Make e820_search_gap() static and remove unused variables") ... defaulting to address 0x10000000 if nothing was found. Signed-off-by: Arnd Bergmann Cc: Dan Williams Cc: Denys Vlasenko Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Toshi Kani Cc: Wei Yang Fixes: b4ed1d15b453 ("x86/e820: Make e820_search_gap() static and remove unused variables") Link: http://lkml.kernel.org/r/20170111144926.695369-1-arnd@arndb.de Signed-off-by: Ingo Molnar --- arch/x86/kernel/e820.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c index 46f2afd3577a..b2bbad6ebe4d 100644 --- a/arch/x86/kernel/e820.c +++ b/arch/x86/kernel/e820.c @@ -626,14 +626,16 @@ __init void e820_setup_gap(void) gapsize = 0x400000; found = e820_search_gap(&gapstart, &gapsize); -#ifdef CONFIG_X86_64 if (!found) { +#ifdef CONFIG_X86_64 gapstart = (max_pfn << PAGE_SHIFT) + 1024*1024; printk(KERN_ERR "e820: cannot find a gap in the 32bit address range\n" "e820: PCI devices with unassigned 32bit BARs may break!\n"); - } +#else + gapstart = 0x10000000; #endif + } /* * e820_reserve_resources_late protect stolen RAM already -- 2.20.1