From 081cd62a010f97b5bc1d2b0cd123c5abc692b68a Mon Sep 17 00:00:00 2001 From: Matt Fleming Date: Tue, 14 Jan 2014 12:40:09 +0000 Subject: [PATCH] x86/efi: Allow mapping BGRT on x86-32 CONFIG_X86_32 doesn't map the boot services regions into the EFI memory map (see commit 700870119f49 ("x86, efi: Don't map Boot Services on i386")), and so efi_lookup_mapped_addr() will fail to return a valid address. Executing the ioremap() path in efi_bgrt_init() causes the following warning on x86-32 because we're trying to ioremap() RAM, WARNING: CPU: 0 PID: 0 at arch/x86/mm/ioremap.c:102 __ioremap_caller+0x2ad/0x2c0() Modules linked in: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.13.0-0.rc5.git0.1.2.fc21.i686 #1 Hardware name: DellInc. Venue 8 Pro 5830/09RP78, BIOS A02 10/17/2013 00000000 00000000 c0c0df08 c09a5196 00000000 c0c0df38 c0448c1e c0b41310 00000000 00000000 c0b37bc1 00000066 c043bbfd c043bbfd 00e7dfe0 00073eff 00073eff c0c0df48 c0448ce2 00000009 00000000 c0c0df9c c043bbfd 00078d88 Call Trace: [] dump_stack+0x41/0x52 [] warn_slowpath_common+0x7e/0xa0 [] ? __ioremap_caller+0x2ad/0x2c0 [] ? __ioremap_caller+0x2ad/0x2c0 [] warn_slowpath_null+0x22/0x30 [] __ioremap_caller+0x2ad/0x2c0 [] ? acpi_tb_verify_table+0x1c/0x43 [] ? acpi_get_table_with_size+0x63/0xb5 [] ? efi_lookup_mapped_addr+0xe/0xf0 [] ioremap_nocache+0x1b/0x20 [] ? efi_bgrt_init+0x83/0x10c [] efi_bgrt_init+0x83/0x10c [] efi_late_init+0x8/0xa [] start_kernel+0x3ae/0x3c3 [] ? repair_env_string+0x51/0x51 [] i386_start_kernel+0x12e/0x131 Switch to using early_memremap(), which won't trigger this warning, and has the added benefit of more accurately conveying what we're trying to do - map a chunk of memory. This patch addresses the following bug report, https://bugzilla.kernel.org/show_bug.cgi?id=67911 Reported-by: Adam Williamson Cc: Josh Triplett Cc: Matthew Garrett Cc: Rafael J. Wysocki Signed-off-by: Matt Fleming --- arch/x86/platform/efi/efi-bgrt.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/arch/x86/platform/efi/efi-bgrt.c b/arch/x86/platform/efi/efi-bgrt.c index 7145ec63c520..4df9591eadad 100644 --- a/arch/x86/platform/efi/efi-bgrt.c +++ b/arch/x86/platform/efi/efi-bgrt.c @@ -49,7 +49,8 @@ void __init efi_bgrt_init(void) image = efi_lookup_mapped_addr(bgrt_tab->image_address); if (!image) { - image = ioremap(bgrt_tab->image_address, sizeof(bmp_header)); + image = early_memremap(bgrt_tab->image_address, + sizeof(bmp_header)); ioremapped = true; if (!image) return; @@ -57,7 +58,7 @@ void __init efi_bgrt_init(void) memcpy_fromio(&bmp_header, image, sizeof(bmp_header)); if (ioremapped) - iounmap(image); + early_iounmap(image, sizeof(bmp_header)); bgrt_image_size = bmp_header.size; bgrt_image = kmalloc(bgrt_image_size, GFP_KERNEL); @@ -65,7 +66,8 @@ void __init efi_bgrt_init(void) return; if (ioremapped) { - image = ioremap(bgrt_tab->image_address, bmp_header.size); + image = early_memremap(bgrt_tab->image_address, + bmp_header.size); if (!image) { kfree(bgrt_image); bgrt_image = NULL; @@ -75,5 +77,5 @@ void __init efi_bgrt_init(void) memcpy_fromio(bgrt_image, image, bgrt_image_size); if (ioremapped) - iounmap(image); + early_iounmap(image, bmp_header.size); }