OpenCloudOS-Kernel/drivers/firmware/efi/arm-runtime.c

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// SPDX-License-Identifier: GPL-2.0
/*
* Extensible Firmware Interface
*
* Based on Extensible Firmware Interface Specification version 2.4
*
* Copyright (C) 2013, 2014 Linaro Ltd.
*/
efi/arm: Enable DMI/SMBIOS Wire up the existing arm64 support for SMBIOS tables (aka DMI) for ARM as well, by moving the arm64 init code to drivers/firmware/efi/arm-runtime.c (which is shared between ARM and arm64), and adding a asm/dmi.h header to ARM that defines the mapping routines for the firmware tables. This allows userspace to access these tables to discover system information exposed by the firmware. It also sets the hardware name used in crash dumps, e.g.: Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = ed3c0000 [00000000] *pgd=bf1f3835 Internal error: Oops: 817 [#1] SMP THUMB2 Modules linked in: CPU: 0 PID: 759 Comm: bash Not tainted 4.10.0-09601-g0e8f38792120-dirty #112 Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 ^^^ NOTE: This does *NOT* enable or encourage the use of DMI quirks, i.e., the the practice of identifying the platform via DMI to decide whether certain workarounds for buggy hardware and/or firmware need to be enabled. This would require the DMI subsystem to be enabled much earlier than we do on ARM, which is non-trivial. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Russell King <rmk+kernel@armlinux.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20170602135207.21708-14-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-02 21:52:07 +08:00
#include <linux/dmi.h>
#include <linux/efi.h>
#include <linux/io.h>
#include <linux/memblock.h>
#include <linux/mm_types.h>
#include <linux/preempt.h>
#include <linux/rbtree.h>
#include <linux/rwsem.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
mm: reorder includes after introduction of linux/pgtable.h The replacement of <asm/pgrable.h> with <linux/pgtable.h> made the include of the latter in the middle of asm includes. Fix this up with the aid of the below script and manual adjustments here and there. import sys import re if len(sys.argv) is not 3: print "USAGE: %s <file> <header>" % (sys.argv[0]) sys.exit(1) hdr_to_move="#include <linux/%s>" % sys.argv[2] moved = False in_hdrs = False with open(sys.argv[1], "r") as f: lines = f.readlines() for _line in lines: line = _line.rstrip(' ') if line == hdr_to_move: continue if line.startswith("#include <linux/"): in_hdrs = True elif not moved and in_hdrs: moved = True print hdr_to_move print line Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Cain <bcain@codeaurora.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Nick Hu <nickhu@andestech.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200514170327.31389-4-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 12:32:42 +08:00
#include <linux/pgtable.h>
#include <asm/cacheflush.h>
#include <asm/efi.h>
#include <asm/mmu.h>
#include <asm/pgalloc.h>
arm64: mm: convert mm/dump.c to use walk_page_range() Now walk_page_range() can walk kernel page tables, we can switch the arm64 ptdump code over to using it, simplifying the code. Link: http://lkml.kernel.org/r/20191218162402.45610-22-steven.price@arm.com Signed-off-by: Steven Price <steven.price@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Hogan <jhogan@kernel.org> Cc: James Morse <james.morse@arm.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: "Liang, Kan" <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Burton <paul.burton@mips.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Cc: Zong Li <zong.li@sifive.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04 09:36:29 +08:00
#if defined(CONFIG_PTDUMP_DEBUGFS) && defined(CONFIG_ARM64)
#include <asm/ptdump.h>
static struct ptdump_info efi_ptdump_info = {
.mm = &efi_mm,
.markers = (struct addr_marker[]){
efi/arm64: Fix debugfs crash by adding a terminator for ptdump marker When reading 'efi_page_tables' debugfs triggers an out-of-bounds access here: arch/arm64/mm/dump.c: 282 if (addr >= st->marker[1].start_address) { called from: arch/arm64/mm/dump.c: 331 note_page(st, addr, 2, pud_val(pud)); because st->marker++ is is called after "UEFI runtime end" which is the last element in addr_marker[]. Therefore, add a terminator like the one for kernel_page_tables, so it can be skipped to print out non-existent markers. Here's the KASAN bug report: # cat /sys/kernel/debug/efi_page_tables ---[ UEFI runtime start ]--- 0x0000000020000000-0x0000000020010000 64K PTE RW NX SHD AF ... 0x0000000020200000-0x0000000021340000 17664K PTE RW NX SHD AF ... ... 0x0000000021920000-0x0000000021950000 192K PTE RW x SHD AF ... 0x0000000021950000-0x00000000219a0000 320K PTE RW NX SHD AF ... ---[ UEFI runtime end ]--- ---[ (null) ]--- ---[ (null) ]--- BUG: KASAN: global-out-of-bounds in note_page+0x1f0/0xac0 Read of size 8 at addr ffff2000123f2ac0 by task read_all/42464 Call trace: dump_backtrace+0x0/0x298 show_stack+0x24/0x30 dump_stack+0xb0/0xdc print_address_description+0x64/0x2b0 kasan_report+0x150/0x1a4 __asan_report_load8_noabort+0x30/0x3c note_page+0x1f0/0xac0 walk_pgd+0xb4/0x244 ptdump_walk_pgd+0xec/0x140 ptdump_show+0x40/0x50 seq_read+0x3f8/0xad0 full_proxy_read+0x9c/0xc0 __vfs_read+0xfc/0x4c8 vfs_read+0xec/0x208 ksys_read+0xd0/0x15c __arm64_sys_read+0x84/0x94 el0_svc_handler+0x258/0x304 el0_svc+0x8/0xc The buggy address belongs to the variable: __compound_literal.0+0x20/0x800 Memory state around the buggy address: ffff2000123f2980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff2000123f2a00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fa >ffff2000123f2a80: fa fa fa fa 00 00 00 00 fa fa fa fa 00 00 00 00 ^ ffff2000123f2b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff2000123f2b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0 [ ardb: fix up whitespace ] [ mingo: fix up some moar ] Signed-off-by: Qian Cai <cai@lca.pw> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Fixes: 9d80448ac92b ("efi/arm64: Add debugfs node to dump UEFI runtime page tables") Link: http://lkml.kernel.org/r/20190202095017.13799-2-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-02 17:50:17 +08:00
{ 0, "UEFI runtime start" },
{ DEFAULT_MAP_WINDOW_64, "UEFI runtime end" },
{ -1, NULL }
},
.base_addr = 0,
};
static int __init ptdump_init(void)
{
if (efi_enabled(EFI_RUNTIME_SERVICES))
ptdump_debugfs_register(&efi_ptdump_info, "efi_page_tables");
efi/arm*: Only register page tables when they exist Currently the arm/arm64 runtime code registers the runtime servies pagetables with ptdump regardless of whether runtime services page tables have been created. As efi_mm.pgd is NULL in these cases, attempting to dump the efi page tables results in a NULL pointer dereference in the ptdump code: /sys/kernel/debug# cat efi_page_tables [ 479.522600] Unable to handle kernel NULL pointer dereference at virtual address 00000000 [ 479.522715] Mem abort info: [ 479.522764] ESR = 0x96000006 [ 479.522850] Exception class = DABT (current EL), IL = 32 bits [ 479.522899] SET = 0, FnV = 0 [ 479.522937] EA = 0, S1PTW = 0 [ 479.528200] Data abort info: [ 479.528230] ISV = 0, ISS = 0x00000006 [ 479.528317] CM = 0, WnR = 0 [ 479.528317] user pgtable: 4k pages, 48-bit VAs, pgd = 0000000064ab0cb0 [ 479.528449] [0000000000000000] *pgd=00000000fbbe4003, *pud=00000000fb66e003, *pmd=0000000000000000 [ 479.528600] Internal error: Oops: 96000006 [#1] PREEMPT SMP [ 479.528664] Modules linked in: [ 479.528699] CPU: 0 PID: 2457 Comm: cat Not tainted 4.15.0-rc3-00065-g2ad2ee7ecb5c-dirty #7 [ 479.528799] Hardware name: FVP Base (DT) [ 479.528899] pstate: 00400009 (nzcv daif +PAN -UAO) [ 479.528941] pc : walk_pgd.isra.1+0x20/0x1d0 [ 479.529011] lr : ptdump_walk_pgd+0x30/0x50 [ 479.529105] sp : ffff00000bf4bc20 [ 479.529185] x29: ffff00000bf4bc20 x28: 0000ffff9d22e000 [ 479.529271] x27: 0000000000020000 x26: ffff80007b4c63c0 [ 479.529358] x25: 00000000014000c0 x24: ffff80007c098900 [ 479.529445] x23: ffff00000bf4beb8 x22: 0000000000000000 [ 479.529532] x21: ffff00000bf4bd70 x20: 0000000000000001 [ 479.529618] x19: ffff00000bf4bcb0 x18: 0000000000000000 [ 479.529760] x17: 000000000041a1c8 x16: ffff0000082139d8 [ 479.529800] x15: 0000ffff9d3c6030 x14: 0000ffff9d2527f4 [ 479.529924] x13: 00000000000003f3 x12: 0000000000000038 [ 479.530000] x11: 0000000000000003 x10: 0101010101010101 [ 479.530099] x9 : 0000000017e94050 x8 : 000000000000003f [ 479.530226] x7 : 0000000000000000 x6 : 0000000000000000 [ 479.530313] x5 : 0000000000000001 x4 : 0000000000000000 [ 479.530416] x3 : ffff000009069fd8 x2 : 0000000000000000 [ 479.530500] x1 : 0000000000000000 x0 : 0000000000000000 [ 479.530599] Process cat (pid: 2457, stack limit = 0x000000005d1b0e6f) [ 479.530660] Call trace: [ 479.530746] walk_pgd.isra.1+0x20/0x1d0 [ 479.530833] ptdump_walk_pgd+0x30/0x50 [ 479.530907] ptdump_show+0x10/0x20 [ 479.530920] seq_read+0xc8/0x470 [ 479.531023] full_proxy_read+0x60/0x90 [ 479.531100] __vfs_read+0x18/0x100 [ 479.531180] vfs_read+0x88/0x160 [ 479.531267] SyS_read+0x48/0xb0 [ 479.531299] el0_svc_naked+0x20/0x24 [ 479.531400] Code: 91400420 f90033a0 a90707a2 f9403fa0 (f9400000) [ 479.531499] ---[ end trace bfe8e28d8acb2b67 ]--- Segmentation fault Let's avoid this problem by only registering the tables after their successful creation, which is also less confusing when EFI runtime services are not in use. Reported-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20180308080020.22828-2-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-08 16:00:09 +08:00
return 0;
}
device_initcall(ptdump_init);
#endif
static bool __init efi_virtmap_init(void)
{
efi_memory_desc_t *md;
efi_mm.pgd = pgd_alloc(&efi_mm);
mm_init_cpumask(&efi_mm);
init_new_context(NULL, &efi_mm);
for_each_efi_memory_desc(md) {
phys_addr_t phys = md->phys_addr;
int ret;
if (!(md->attribute & EFI_MEMORY_RUNTIME))
continue;
if (md->virt_addr == 0)
return false;
ret = efi_create_mapping(&efi_mm, md);
if (ret) {
pr_warn(" EFI remap %pa: failed to create mapping (%d)\n",
&phys, ret);
return false;
}
}
if (efi_memattr_apply_permissions(&efi_mm, efi_set_mapping_permissions))
return false;
return true;
}
/*
* Enable the UEFI Runtime Services if all prerequisites are in place, i.e.,
* non-early mapping of the UEFI system table and virtual mappings for all
* EFI_MEMORY_RUNTIME regions.
*/
static int __init arm_enable_runtime_services(void)
{
u64 mapsize;
if (!efi_enabled(EFI_BOOT)) {
pr_info("EFI services will not be available.\n");
return 0;
}
efi_memmap_unmap();
mapsize = efi.memmap.desc_size * efi.memmap.nr_map;
if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) {
pr_err("Failed to remap EFI memory map\n");
return 0;
}
if (efi_soft_reserve_enabled()) {
efi_memory_desc_t *md;
for_each_efi_memory_desc(md) {
int md_size = md->num_pages << EFI_PAGE_SHIFT;
struct resource *res;
if (!(md->attribute & EFI_MEMORY_SP))
continue;
res = kzalloc(sizeof(*res), GFP_KERNEL);
if (WARN_ON(!res))
break;
res->start = md->phys_addr;
res->end = md->phys_addr + md_size - 1;
res->name = "Soft Reserved";
res->flags = IORESOURCE_MEM;
res->desc = IORES_DESC_SOFT_RESERVED;
insert_resource(&iomem_resource, res);
}
}
if (efi_runtime_disabled()) {
pr_info("EFI runtime services will be disabled.\n");
return 0;
}
if (efi_enabled(EFI_RUNTIME_SERVICES)) {
pr_info("EFI runtime services access via paravirt.\n");
return 0;
}
pr_info("Remapping and enabling EFI services.\n");
if (!efi_virtmap_init()) {
efi/arm*: Drop writable mapping of the UEFI System table Commit: 2eec5dedf770 ("efi/arm-init: Use read-only early mappings") updated the early ARM UEFI init code to create the temporary, early mapping of the UEFI System table using read-only attributes, as a hardening measure against inadvertent modification. However, this still leaves the permanent, writable mapping of the UEFI System table, which is only ever referenced during invocations of UEFI Runtime Services, at which time the UEFI virtual mapping is available, which also covers the system table. (This is guaranteed by the fact that SetVirtualAddressMap(), which is a runtime service itself, converts various entries in the table to their virtual equivalents, which implies that the table must be covered by a RuntimeServicesData region that has the EFI_MEMORY_RUNTIME attribute.) So instead of creating this permanent mapping, record the virtual address of the system table inside the UEFI virtual mapping, and dereference that when accessing the table. This protects the contents of the system table from inadvertent (or deliberate) modification when no UEFI Runtime Services calls are in progress. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-3-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-26 04:06:34 +08:00
pr_err("UEFI virtual mapping missing or invalid -- runtime services will not be available\n");
return -ENOMEM;
}
/* Set up runtime services function pointers */
efi_native_runtime_setup();
set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
return 0;
}
early_initcall(arm_enable_runtime_services);
void efi_virtmap_load(void)
{
preempt_disable();
efi_set_pgd(&efi_mm);
}
void efi_virtmap_unload(void)
{
efi_set_pgd(current->active_mm);
preempt_enable();
}
efi/arm: Enable DMI/SMBIOS Wire up the existing arm64 support for SMBIOS tables (aka DMI) for ARM as well, by moving the arm64 init code to drivers/firmware/efi/arm-runtime.c (which is shared between ARM and arm64), and adding a asm/dmi.h header to ARM that defines the mapping routines for the firmware tables. This allows userspace to access these tables to discover system information exposed by the firmware. It also sets the hardware name used in crash dumps, e.g.: Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = ed3c0000 [00000000] *pgd=bf1f3835 Internal error: Oops: 817 [#1] SMP THUMB2 Modules linked in: CPU: 0 PID: 759 Comm: bash Not tainted 4.10.0-09601-g0e8f38792120-dirty #112 Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 ^^^ NOTE: This does *NOT* enable or encourage the use of DMI quirks, i.e., the the practice of identifying the platform via DMI to decide whether certain workarounds for buggy hardware and/or firmware need to be enabled. This would require the DMI subsystem to be enabled much earlier than we do on ARM, which is non-trivial. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Russell King <rmk+kernel@armlinux.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20170602135207.21708-14-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-02 21:52:07 +08:00
static int __init arm_dmi_init(void)
{
/*
* On arm64/ARM, DMI depends on UEFI, and dmi_setup() needs to
efi/arm: Enable DMI/SMBIOS Wire up the existing arm64 support for SMBIOS tables (aka DMI) for ARM as well, by moving the arm64 init code to drivers/firmware/efi/arm-runtime.c (which is shared between ARM and arm64), and adding a asm/dmi.h header to ARM that defines the mapping routines for the firmware tables. This allows userspace to access these tables to discover system information exposed by the firmware. It also sets the hardware name used in crash dumps, e.g.: Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = ed3c0000 [00000000] *pgd=bf1f3835 Internal error: Oops: 817 [#1] SMP THUMB2 Modules linked in: CPU: 0 PID: 759 Comm: bash Not tainted 4.10.0-09601-g0e8f38792120-dirty #112 Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 ^^^ NOTE: This does *NOT* enable or encourage the use of DMI quirks, i.e., the the practice of identifying the platform via DMI to decide whether certain workarounds for buggy hardware and/or firmware need to be enabled. This would require the DMI subsystem to be enabled much earlier than we do on ARM, which is non-trivial. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Russell King <rmk+kernel@armlinux.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20170602135207.21708-14-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-02 21:52:07 +08:00
* be called early because dmi_id_init(), which is an arch_initcall
* itself, depends on dmi_scan_machine() having been called already.
*/
dmi_setup();
efi/arm: Enable DMI/SMBIOS Wire up the existing arm64 support for SMBIOS tables (aka DMI) for ARM as well, by moving the arm64 init code to drivers/firmware/efi/arm-runtime.c (which is shared between ARM and arm64), and adding a asm/dmi.h header to ARM that defines the mapping routines for the firmware tables. This allows userspace to access these tables to discover system information exposed by the firmware. It also sets the hardware name used in crash dumps, e.g.: Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = ed3c0000 [00000000] *pgd=bf1f3835 Internal error: Oops: 817 [#1] SMP THUMB2 Modules linked in: CPU: 0 PID: 759 Comm: bash Not tainted 4.10.0-09601-g0e8f38792120-dirty #112 Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 ^^^ NOTE: This does *NOT* enable or encourage the use of DMI quirks, i.e., the the practice of identifying the platform via DMI to decide whether certain workarounds for buggy hardware and/or firmware need to be enabled. This would require the DMI subsystem to be enabled much earlier than we do on ARM, which is non-trivial. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Russell King <rmk+kernel@armlinux.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20170602135207.21708-14-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-02 21:52:07 +08:00
return 0;
}
core_initcall(arm_dmi_init);