| From e2c90dd7e11e3025b46719a79fb4bb1e7a5cef9f Mon Sep 17 00:00:00 2001 |
| From: Matt Fleming <matt@codeblueprint.co.uk> |
| Date: Mon, 21 Dec 2015 14:12:52 +0000 |
| Subject: x86/efi-bgrt: Replace early_memremap() with memremap() |
| MIME-Version: 1.0 |
| Content-Type: text/plain; charset=UTF-8 |
| Content-Transfer-Encoding: 8bit |
| |
| From: Matt Fleming <matt@codeblueprint.co.uk> |
| |
| commit e2c90dd7e11e3025b46719a79fb4bb1e7a5cef9f upstream. |
| |
| Môshe reported the following warning triggered on his machine since |
| commit 50a0cb565246 ("x86/efi-bgrt: Fix kernel panic when mapping BGRT |
| data"), |
| |
| [ 0.026936] ------------[ cut here ]------------ |
| [ 0.026941] WARNING: CPU: 0 PID: 0 at mm/early_ioremap.c:137 __early_ioremap+0x102/0x1bb() |
| [ 0.026941] Modules linked in: |
| [ 0.026944] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.4.0-rc1 #2 |
| [ 0.026945] Hardware name: Dell Inc. XPS 13 9343/09K8G1, BIOS A05 07/14/2015 |
| [ 0.026946] 0000000000000000 900f03d5a116524d ffffffff81c03e60 ffffffff813a3fff |
| [ 0.026948] 0000000000000000 ffffffff81c03e98 ffffffff810a0852 00000000d7b76000 |
| [ 0.026949] 0000000000000000 0000000000000001 0000000000000001 000000000000017c |
| [ 0.026951] Call Trace: |
| [ 0.026955] [<ffffffff813a3fff>] dump_stack+0x44/0x55 |
| [ 0.026958] [<ffffffff810a0852>] warn_slowpath_common+0x82/0xc0 |
| [ 0.026959] [<ffffffff810a099a>] warn_slowpath_null+0x1a/0x20 |
| [ 0.026961] [<ffffffff81d8c395>] __early_ioremap+0x102/0x1bb |
| [ 0.026962] [<ffffffff81d8c602>] early_memremap+0x13/0x15 |
| [ 0.026964] [<ffffffff81d78361>] efi_bgrt_init+0x162/0x1ad |
| [ 0.026966] [<ffffffff81d778ec>] efi_late_init+0x9/0xb |
| [ 0.026968] [<ffffffff81d58ff5>] start_kernel+0x46f/0x49f |
| [ 0.026970] [<ffffffff81d58120>] ? early_idt_handler_array+0x120/0x120 |
| [ 0.026972] [<ffffffff81d58339>] x86_64_start_reservations+0x2a/0x2c |
| [ 0.026974] [<ffffffff81d58485>] x86_64_start_kernel+0x14a/0x16d |
| [ 0.026977] ---[ end trace f9b3812eb8e24c58 ]--- |
| [ 0.026978] efi_bgrt: Ignoring BGRT: failed to map image memory |
| |
| early_memremap() has an upper limit on the size of mapping it can |
| handle which is ~200KB. Clearly the BGRT image on Môshe's machine is |
| much larger than that. |
| |
| There's actually no reason to restrict ourselves to using the early_* |
| version of memremap() - the ACPI BGRT driver is invoked late enough in |
| boot that we can use the standard version, with the benefit that the |
| late version allows mappings of arbitrary size. |
| |
| Reported-by: Môshe van der Sterre <me@moshe.nl> |
| Tested-by: Môshe van der Sterre <me@moshe.nl> |
| Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> |
| Cc: Josh Triplett <josh@joshtriplett.org> |
| Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> |
| Cc: Borislav Petkov <bp@suse.de> |
| Link: http://lkml.kernel.org/r/1450707172-12561-1-git-send-email-matt@codeblueprint.co.uk |
| Signed-off-by: Thomas Gleixner <tglx@linutronix.de> |
| Cc: "Ghannam, Yazen" <Yazen.Ghannam@amd.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| arch/x86/platform/efi/efi-bgrt.c | 8 ++++---- |
| 1 file changed, 4 insertions(+), 4 deletions(-) |
| |
| --- a/arch/x86/platform/efi/efi-bgrt.c |
| +++ b/arch/x86/platform/efi/efi-bgrt.c |
| @@ -69,14 +69,14 @@ void __init efi_bgrt_init(void) |
| return; |
| } |
| |
| - image = early_memremap(bgrt_tab->image_address, sizeof(bmp_header)); |
| + image = memremap(bgrt_tab->image_address, sizeof(bmp_header), MEMREMAP_WB); |
| if (!image) { |
| pr_err("Ignoring BGRT: failed to map image header memory\n"); |
| return; |
| } |
| |
| memcpy(&bmp_header, image, sizeof(bmp_header)); |
| - early_memunmap(image, sizeof(bmp_header)); |
| + memunmap(image); |
| bgrt_image_size = bmp_header.size; |
| |
| bgrt_image = kmalloc(bgrt_image_size, GFP_KERNEL | __GFP_NOWARN); |
| @@ -86,7 +86,7 @@ void __init efi_bgrt_init(void) |
| return; |
| } |
| |
| - image = early_memremap(bgrt_tab->image_address, bmp_header.size); |
| + image = memremap(bgrt_tab->image_address, bmp_header.size, MEMREMAP_WB); |
| if (!image) { |
| pr_err("Ignoring BGRT: failed to map image memory\n"); |
| kfree(bgrt_image); |
| @@ -95,5 +95,5 @@ void __init efi_bgrt_init(void) |
| } |
| |
| memcpy(bgrt_image, image, bgrt_image_size); |
| - early_memunmap(image, bmp_header.size); |
| + memunmap(image); |
| } |