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2019-01-11x86/kdump: Export the SME mask to vmcoreinfoLianbo Jiang1-0/+3
On AMD SME machines, makedumpfile tools need to know whether the crashed kernel was encrypted. If SME is enabled in the first kernel, the crashed kernel's page table entries (pgd/pud/pmd/pte) contain the memory encryption mask which makedumpfile needs to remove in order to obtain the true physical address. Export that mask in a vmcoreinfo variable. [ bp: Massage commit message and move define at the end of the function. ] Signed-off-by: Lianbo Jiang <lijiang@redhat.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Baoquan He <bhe@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: anderson@redhat.com Cc: k-hagio@ab.jp.nec.com Cc: kexec@lists.infradead.org Cc: linux-doc@vger.kernel.org Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20190110121944.6050-3-lijiang@redhat.com
2018-05-19x86/mm: Stop pretending pgtable_l5_enabled is a variableKirill A. Shutemov1-1/+2
pgtable_l5_enabled is defined using cpu_feature_enabled() but we refer to it as a variable. This is misleading. Make pgtable_l5_enabled() a function. We cannot literally define it as a function due to circular dependencies between header files. Function-alike macros is close enough. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Hugh Dickins <hughd@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20180518103528.59260-4-kirill.shutemov@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-13x86/kexec: Avoid double free_page() upon do_kexec_load() failureTetsuo Handa1-1/+4
>From ff82bedd3e12f0d3353282054ae48c3bd8c72012 Mon Sep 17 00:00:00 2001 From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Date: Wed, 9 May 2018 12:12:39 +0900 Subject: [PATCH v3] x86/kexec: avoid double free_page() upon do_kexec_load() failure. syzbot is reporting crashes after memory allocation failure inside do_kexec_load() [1]. This is because free_transition_pgtable() is called by both init_transition_pgtable() and machine_kexec_cleanup() when memory allocation failed inside init_transition_pgtable(). Regarding 32bit code, machine_kexec_free_page_tables() is called by both machine_kexec_alloc_page_tables() and machine_kexec_cleanup() when memory allocation failed inside machine_kexec_alloc_page_tables(). Fix this by leaving the error handling to machine_kexec_cleanup() (and optionally setting NULL after free_page()). [1] https://syzkaller.appspot.com/bug?id=91e52396168cf2bdd572fe1e1bc0bc645c1c6b40 Fixes: f5deb79679af6eb4 ("x86: kexec: Use one page table in x86_64 machine_kexec") Fixes: 92be3d6bdf2cb349 ("kexec/i386: allocate page table pages dynamically") Reported-by: syzbot <syzbot+d96f60296ef613fe1d69@syzkaller.appspotmail.com> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Baoquan He <bhe@redhat.com> Cc: thomas.lendacky@amd.com Cc: prudo@linux.vnet.ibm.com Cc: Huang Ying <ying.huang@intel.com> Cc: syzkaller-bugs@googlegroups.com Cc: takahiro.akashi@linaro.org Cc: H. Peter Anvin <hpa@zytor.com> Cc: akpm@linux-foundation.org Cc: dyoung@redhat.com Cc: kirill.shutemov@linux.intel.com Link: https://lkml.kernel.org/r/201805091942.DGG12448.tMFVFSJFQOOLHO@I-love.SAKURA.ne.jp
2018-04-13kernel/kexec_file.c: remove mis-use of sh_offset field during purgatory loadPhilipp Rudo1-4/+6
The current code uses the sh_offset field in purgatory_info->sechdrs to store a pointer to the current load address of the section. Depending whether the section will be loaded or not this is either a pointer into purgatory_info->purgatory_buf or kexec_purgatory. This is not only a violation of the ELF standard but also makes the code very hard to understand as you cannot tell if the memory you are using is read-only or not. Remove this misuse and store the offset of the section in pugaroty_info->purgatory_buf in sh_offset. Link: http://lkml.kernel.org/r/20180321112751.22196-10-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13kernel/kexec_file.c: use read-only sections in arch_kexec_apply_relocations*Philipp Rudo1-36/+20
When the relocations are applied to the purgatory only the section the relocations are applied to is writable. The other sections, i.e. the symtab and .rel/.rela, are in read-only kexec_purgatory. Highlight this by marking the corresponding variables as 'const'. While at it also change the signatures of arch_kexec_apply_relocations* to take section pointers instead of just the index of the relocation section. This removes the second lookup and sanity check of the sections in arch code. Link: http://lkml.kernel.org/r/20180321112751.22196-6-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13kexec_file,x86,powerpc: factor out kexec_file_ops functionsAKASHI Takahiro1-43/+2
As arch_kexec_kernel_image_{probe,load}(), arch_kimage_file_post_load_cleanup() and arch_kexec_kernel_verify_sig() are almost duplicated among architectures, they can be commonalized with an architecture-defined kexec_file_ops array. So let's factor them out. Link: http://lkml.kernel.org/r/20180306102303.9063-3-takahiro.akashi@linaro.org Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Acked-by: Dave Young <dyoung@redhat.com> Tested-by: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-02Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mm updates from Ingo Molnar: - Extend the memmap= boot parameter syntax to allow the redeclaration and dropping of existing ranges, and to support all e820 range types (Jan H. Schönherr) - Improve the W+X boot time security checks to remove false positive warnings on Xen (Jan Beulich) - Support booting as Xen PVH guest (Juergen Gross) - Improved 5-level paging (LA57) support, in particular it's possible now to have a single kernel image for both 4-level and 5-level hardware (Kirill A. Shutemov) - AMD hardware RAM encryption support (SME/SEV) fixes (Tom Lendacky) - Preparatory commits for hardware-encrypted RAM support on Intel CPUs. (Kirill A. Shutemov) - Improved Intel-MID support (Andy Shevchenko) - Show EFI page tables in page_tables debug files (Andy Lutomirski) - ... plus misc fixes and smaller cleanups * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (56 commits) x86/cpu/tme: Fix spelling: "configuation" -> "configuration" x86/boot: Fix SEV boot failure from change to __PHYSICAL_MASK_SHIFT x86/mm: Update comment in detect_tme() regarding x86_phys_bits x86/mm/32: Remove unused node_memmap_size_bytes() & CONFIG_NEED_NODE_MEMMAP_SIZE logic x86/mm: Remove pointless checks in vmalloc_fault x86/platform/intel-mid: Add special handling for ACPI HW reduced platforms ACPI, x86/boot: Introduce the ->reduced_hw_early_init() ACPI callback ACPI, x86/boot: Split out acpi_generic_reduce_hw_init() and export x86/pconfig: Provide defines and helper to run MKTME_KEY_PROG leaf x86/pconfig: Detect PCONFIG targets x86/tme: Detect if TME and MKTME is activated by BIOS x86/boot/compressed/64: Handle 5-level paging boot if kernel is above 4G x86/boot/compressed/64: Use page table in trampoline memory x86/boot/compressed/64: Use stack from trampoline memory x86/boot/compressed/64: Make sure we have a 32-bit code segment x86/mm: Do not use paravirtualized calls in native_set_p4d() kdump, vmcoreinfo: Export pgtable_l5_enabled value x86/boot/compressed/64: Prepare new top-level page table for trampoline x86/boot/compressed/64: Set up trampoline memory x86/boot/compressed/64: Save and restore trampoline memory ...
2018-04-02Merge branch 'x86-apic-for-linus' of ↵Linus Torvalds1-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 apic updates from Ingo Molnar: "The main x86 APIC/IOAPIC changes in this cycle were: - Robustify kexec support to more carefully restore IRQ hardware state before calling into kexec/kdump kernels. (Baoquan He) - Clean up the local APIC code a bit (Dou Liyang) - Remove unused callbacks (David Rientjes)" * 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/apic: Finish removing unused callbacks x86/apic: Drop logical_smp_processor_id() inline x86/apic: Modernize the pending interrupt code x86/apic: Move pending interrupt check code into it's own function x86/apic: Set up through-local-APIC mode on the boot CPU if 'noapic' specified x86/apic: Rename variables and functions related to x86_io_apic_ops x86/apic: Remove the (now) unused disable_IO_APIC() function x86/apic: Fix restoring boot IRQ mode in reboot and kexec/kdump x86/apic: Split disable_IO_APIC() into two functions to fix CONFIG_KEXEC_JUMP=y x86/apic: Split out restore_boot_irq_mode() from disable_IO_APIC() x86/apic: Make setup_local_APIC() static x86/apic: Simplify init_bsp_APIC() usage x86/x2apic: Mark set_x2apic_phys_mode() as __init
2018-03-12kdump, vmcoreinfo: Export pgtable_l5_enabled valueBaoquan He1-0/+1
User-space utilities examining crash-kernels need to know if the crashed kernel was in 5-level paging mode or not. So write 'pgtable_l5_enabled' to vmcoreinfo, which covers these three cases: pgtable_l5_enabled == 0 when: - Compiled with !CONFIG_X86_5LEVEL - Compiled with CONFIG_X86_5LEVEL=y while CPU has no 'la57' flag pgtable_l5_enabled != 0 when: - Compiled with CONFIG_X86_5LEVEL=y and CPU has 'la57' flag Signed-off-by: Baoquan He <bhe@redhat.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: douly.fnst@cn.fujitsu.com Cc: dyoung@redhat.com Cc: ebiederm@xmission.com Cc: kirill.shutemov@linux.intel.com Cc: vgoyal@redhat.com Link: http://lkml.kernel.org/r/20180302051801.19594-1-bhe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-22x86: Treat R_X86_64_PLT32 as R_X86_64_PC32H.J. Lu1-0/+1
On i386, there are 2 types of PLTs, PIC and non-PIC. PIE and shared objects must use PIC PLT. To use PIC PLT, you need to load _GLOBAL_OFFSET_TABLE_ into EBX first. There is no need for that on x86-64 since x86-64 uses PC-relative PLT. On x86-64, for 32-bit PC-relative branches, we can generate PLT32 relocation, instead of PC32 relocation, which can also be used as a marker for 32-bit PC-relative branches. Linker can always reduce PLT32 relocation to PC32 if function is defined locally. Local functions should use PC32 relocation. As far as Linux kernel is concerned, R_X86_64_PLT32 can be treated the same as R_X86_64_PC32 since Linux kernel doesn't use PLT. R_X86_64_PLT32 for 32-bit PC-relative branches has been enabled in binutils master branch which will become binutils 2.31. [ hjl is working on having better documentation on this all, but a few more notes from him: "PLT32 relocation is used as marker for PC-relative branches. Because of EBX, it looks odd to generate PLT32 relocation on i386 when EBX doesn't have GOT. As for symbol resolution, PLT32 and PC32 relocations are almost interchangeable. But when linker sees PLT32 relocation against a protected symbol, it can resolved locally at link-time since it is used on a branch instruction. Linker can't do that for PC32 relocation" but for the kernel use, the two are basically the same, and this commit gets things building and working with the current binutils master - Linus ] Signed-off-by: H.J. Lu <hjl.tools@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-17x86/apic: Remove the (now) unused disable_IO_APIC() functionBaoquan He1-3/+2
No one uses it anymore. Signed-off-by: Baoquan He <bhe@redhat.com> Reviewed-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: douly.fnst@cn.fujitsu.com Cc: joro@8bytes.org Cc: prarit@redhat.com Cc: uobergfe@redhat.com Link: http://lkml.kernel.org/r/20180214054656.3780-5-bhe@redhat.com [ Rewrote the changelog. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-17x86/apic: Split disable_IO_APIC() into two functions to fix CONFIG_KEXEC_JUMP=yBaoquan He1-1/+2
Split following patches disable_IO_APIC() will be broken up into clear_IO_APIC() and restore_boot_irq_mode(). These two functions will be called separately where they are needed to fix a regression introduced by: 522e66464467 ("x86/apic: Disable I/O APIC before shutdown of the local APIC"). While the CONFIG_KEXEC_JUMP=y code doesn't call lapic_shutdown() before jump like kexec/kdump, so it's not impacted by commit 522e66464467. Hence here change clear_IO_APIC() as public, and replace disable_IO_APIC() with clear_IO_APIC() and restore_boot_irq_mode() to keep CONFIG_KEXEC_JUMP=y code unchanged in essence. No functional change. Signed-off-by: Baoquan He <bhe@redhat.com> Reviewed-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: douly.fnst@cn.fujitsu.com Cc: joro@8bytes.org Cc: prarit@redhat.com Cc: uobergfe@redhat.com Link: http://lkml.kernel.org/r/20180214054656.3780-3-bhe@redhat.com [ Rewrote the changelog. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-30x86/mm, kexec: Fix memory corruption with SME on successive kexecsTom Lendacky1-1/+2
After issuing successive kexecs it was found that the SHA hash failed verification when booting the kexec'd kernel. When SME is enabled, the change from using pages that were marked encrypted to now being marked as not encrypted (through new identify mapped page tables) results in memory corruption if there are any cache entries for the previously encrypted pages. This is because separate cache entries can exist for the same physical location but tagged both with and without the encryption bit. To prevent this, issue a wbinvd if SME is active before copying the pages from the source location to the destination location to clear any possible cache entry conflicts. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: <kexec@lists.infradead.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: Dave Young <dyoung@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/e7fb8610af3a93e8f8ae6f214cd9249adc0df2b4.1501186516.git.thomas.lendacky@amd.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-18x86/mm, kexec: Allow kexec to be used with SMETom Lendacky1-1/+21
Provide support so that kexec can be used to boot a kernel when SME is enabled. Support is needed to allocate pages for kexec without encryption. This is needed in order to be able to reboot in the kernel in the same manner as originally booted. Additionally, when shutting down all of the CPUs we need to be sure to flush the caches and then halt. This is needed when booting from a state where SME was not active into a state where SME is active (or vice-versa). Without these steps, it is possible for cache lines to exist for the same physical location but tagged both with and without the encryption bit. This can cause random memory corruption when caches are flushed depending on which cacheline is written last. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: <kexec@lists.infradead.org> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: Dave Young <dyoung@redhat.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Toshimitsu Kani <toshi.kani@hpe.com> Cc: kasan-dev@googlegroups.com Cc: kvm@vger.kernel.org Cc: linux-arch@vger.kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-efi@vger.kernel.org Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/b95ff075db3e7cd545313f2fb609a49619a09625.1500319216.git.thomas.lendacky@amd.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-13x86/boot/64: Rename init_level4_pgt and early_level4_pgtKirill A. Shutemov1-1/+1
With CONFIG_X86_5LEVEL=y, level 4 is no longer top level of page tables. Let's give these variable more generic names: init_top_pgt and early_top_pgt. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20170606113133.22974-9-kirill.shutemov@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-12Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds1-1/+5
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Misc fixes: - two boot crash fixes - unwinder fixes - kexec related kernel direct mappings enhancements/fixes - more Clang support quirks - minor cleanups - Documentation fixes" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/intel_rdt: Fix a typo in Documentation x86/build: Don't add -maccumulate-outgoing-args w/o compiler support x86/boot/32: Fix UP boot on Quark and possibly other platforms x86/mm/32: Set the '__vmalloc_start_set' flag in initmem_init() x86/kexec/64: Use gbpages for identity mappings if available x86/mm: Add support for gbpages to kernel_ident_mapping_init() x86/boot: Declare error() as noreturn x86/mm/kaslr: Use the _ASM_MUL macro for multiplication to work around Clang incompatibility x86/mm: Fix boot crash caused by incorrect loop count calculation in sync_global_pgds() x86/asm: Don't use RBP as a temporary register in csum_partial_copy_generic() x86/microcode/AMD: Remove redundant NULL check on mc
2017-05-08x86: use set_memory.h headerLaura Abbott1-0/+1
set_memory_* functions have moved to set_memory.h. Switch to this explicitly. Link: http://lkml.kernel.org/r/1488920133-27229-6-git-send-email-labbott@redhat.com Signed-off-by: Laura Abbott <labbott@redhat.com> Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08x86/kexec/64: Use gbpages for identity mappings if availableXunlei Pang1-0/+4
Kexec sets up all identity mappings before booting into the new kernel, and this will cause extra memory consumption for paging structures which is quite considerable on modern machines with huge memory sizes. E.g. on a 32TB machine that is kdumping, it could waste around 128MB (around 4MB/TB) from the reserved memory after kexec sets all the identity mappings using the current 2MB page. Add to that the memory needed for the loaded kdump kernel, initramfs, etc., and it causes a kexec syscall -NOMEM failure. As a result, we had to enlarge reserved memory via "crashkernel=X" to work around this problem. This causes some trouble for distributions that use policies to evaluate the proper "crashkernel=X" value for users. So enable gbpages for kexec mappings. Signed-off-by: Xunlei Pang <xlpang@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Young <dyoung@redhat.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: akpm@linux-foundation.org Cc: kexec@lists.infradead.org Link: http://lkml.kernel.org/r/1493862171-8799-2-git-send-email-xlpang@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-08x86/mm: Add support for gbpages to kernel_ident_mapping_init()Xunlei Pang1-1/+1
Kernel identity mappings on x86-64 kernels are created in two ways: by the early x86 boot code, or by kernel_ident_mapping_init(). Native kernels (which is the dominant usecase) use the former, but the kexec and the hibernation code uses kernel_ident_mapping_init(). There's a subtle difference between these two ways of how identity mappings are created, the current kernel_ident_mapping_init() code creates identity mappings always using 2MB page(PMD level) - while the native kernel boot path also utilizes gbpages where available. This difference is suboptimal both for performance and for memory usage: kernel_ident_mapping_init() needs to allocate pages for the page tables when creating the new identity mappings. This patch adds 1GB page(PUD level) support to kernel_ident_mapping_init() to address these concerns. The primary advantage would be better TLB coverage/performance, because we'd utilize 1GB TLBs instead of 2MB ones. It is also useful for machines with large number of memory to save paging structure allocations(around 4MB/TB using 2MB page) when setting identity mappings for all the memory, after using 1GB page it will consume only 8KB/TB. ( Note that this change alone does not activate gbpages in kexec, we are doing that in a separate patch. ) Signed-off-by: Xunlei Pang <xlpang@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Young <dyoung@redhat.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yinghai Lu <yinghai@kernel.org> Cc: akpm@linux-foundation.org Cc: kexec@lists.infradead.org Link: http://lkml.kernel.org/r/1493862171-8799-1-git-send-email-xlpang@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-27x86/kexec: Add 5-level paging supportKirill A. Shutemov1-2/+12
Handle additional page table level in the kexec code. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-arch@vger.kernel.org Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20170317185515.8636-2-kirill.shutemov@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-10kexec, x86/purgatory: Unbreak it and clean it upThomas Gleixner1-3/+6
The purgatory code defines global variables which are referenced via a symbol lookup in the kexec code (core and arch). A recent commit addressing sparse warnings made these static and thereby broke kexec_file. Why did this happen? Simply because the whole machinery is undocumented and lacks any form of forward declarations. The variable names are unspecific and lack a prefix, so adding forward declarations creates shadow variables in the core code. Aside of that the code relies on magic constants and duplicate struct definitions with no way to ensure that these things stay in sync. The section placement of the purgatory variables happened by chance and not by design. Unbreak kexec and cleanup the mess: - Add proper forward declarations and document the usage - Use common struct definition - Use the proper common defines instead of magic constants - Add a purgatory_ prefix to have a proper name space - Use ARRAY_SIZE() instead of a homebrewn reimplementation - Add proper sections to the purgatory variables [ From Mike ] Fixes: 72042a8c7b01 ("x86/purgatory: Make functions and variables static") Reported-by: Mike Galbraith <<efault@gmx.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Nicholas Mc Guire <der.herr@hofr.at> Cc: Borislav Petkov <bp@alien8.de> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: "Tobin C. Harding" <me@tobin.cc> Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1703101315140.3681@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-14kexec: export the value of phys_base instead of symbol addressBaoquan He1-1/+2
Currently in x86_64, the symbol address of phys_base is exported to vmcoreinfo. Dave Anderson complained this is really useless for his Crash implementation. Because in user-space utility Crash and Makedumpfile which exported vmcore information is mainly used for, value of phys_base is needed to covert virtual address of exported kernel symbol to physical address. Especially init_level4_pgt, if we want to access and go over the page table to look up a PA corresponding to VA, firstly we need calculate page_dir = SYMBOL(init_level4_pgt) - __START_KERNEL_map + phys_base; Now in Crash and Makedumpfile, we have to analyze the vmcore elf program header to get value of phys_base. As Dave said, it would be preferable if it were readily availabl in vmcoreinfo rather than depending upon the PT_LOAD semantics. Hence in this patch change to export the value of phys_base instead of its virtual address. And people also complained that KERNEL_IMAGE_SIZE exporting is x86_64 only, should be moved into arch dependent function arch_crash_save_vmcoreinfo. Do the moving in this patch. Link: http://lkml.kernel.org/r/1478568596-30060-2-git-send-email-bhe@redhat.com Signed-off-by: Baoquan He <bhe@redhat.com> Cc: Thomas Garnier <thgarnie@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Xunlei Pang <xlpang@redhat.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Kees Cook <keescook@chromium.org> Cc: Eugene Surovegin <surovegin@google.com> Cc: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Atsushi Kumagai <ats-kumagai@wm.jp.nec.com> Cc: Dave Anderson <anderson@redhat.com> Cc: Pratyush Anand <panand@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-14Revert "kdump, vmcoreinfo: report memory sections virtual addresses"Baoquan He1-3/+0
This reverts commit 0549a3c02efb ("kdump, vmcoreinfo: report memory sections virtual addresses"). Commit 0549a3c02efb tells the userspace utility makedumpfile the randomized base address of these memmory sections when mm kaslr is enabled. However the following patch "kexec: export the value of phys_base instead of symbol address" makes makedumpfile not need these addresses any more. Besides we should use VMCOREINFO_NUMBER to export the value of the variable so that we can use the existing number_table mechanism of Makedumpfile to fetch it. So revert it now. If needed we can add it later. http://lists.infradead.org/pipermail/kexec/2016-October/017540.html Link: http://lkml.kernel.org/r/1478568596-30060-1-git-send-email-bhe@redhat.com Signed-off-by: Baoquan He <bhe@redhat.com> Cc: Thomas Garnier <thgarnie@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Xunlei Pang <xlpang@redhat.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Kees Cook <keescook@chromium.org> Cc: Eugene Surovegin <surovegin@google.com> Cc: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Atsushi Kumagai <ats-kumagai@wm.jp.nec.com> Cc: Dave Anderson <anderson@redhat.com> Cc: Pratyush Anand <panand@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11kdump, vmcoreinfo: report memory sections virtual addressesThomas Garnier1-0/+3
KASLR memory randomization can randomize the base of the physical memory mapping (PAGE_OFFSET), vmalloc (VMALLOC_START) and vmemmap (VMEMMAP_START). Adding these variables on VMCOREINFO so tools can easily identify the base of each memory section. Link: http://lkml.kernel.org/r/1471531632-23003-1-git-send-email-thgarnie@google.com Signed-off-by: Thomas Garnier <thgarnie@google.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Xunlei Pang <xlpang@redhat.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Kees Cook <keescook@chromium.org> Cc: Eugene Surovegin <surovegin@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-23kexec: provide arch_kexec_protect(unprotect)_crashkres()Xunlei Pang1-0/+45
Implement the protection method for the crash kernel memory reservation for the 64-bit x86 kdump. Signed-off-by: Xunlei Pang <xlpang@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Dave Young <dyoung@redhat.com> Cc: Minfei Huang <mhuang@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-20kexec: move some memembers and definitions within the scope of CONFIG_KEXEC_FILEXunlei Pang1-0/+2
Move the stuff currently only used by the kexec file code within CONFIG_KEXEC_FILE (and CONFIG_KEXEC_VERIFY_SIG). Also move internal "struct kexec_sha_region" and "struct kexec_buf" into "kexec_internal.h". Signed-off-by: Xunlei Pang <xlpang@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Dave Young <dyoung@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-23Merge branch 'for-linus' of ↵Linus Torvalds1-1/+2
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching Pull livepatching fixes from Jiri Kosina: - symbol lookup locking fix, from Miroslav Benes - error handling improvements in case of failure of the module coming notifier, from Minfei Huang - we were too pessimistic when kASLR has been enabled on x86 and were dropping address hints on the floor unnecessarily in such case. Fix from Jiri Kosina - a few other small fixes and cleanups * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching: livepatch: add module locking around kallsyms calls livepatch: annotate klp_init() with __init livepatch: introduce patch/func-walking helpers livepatch: make kobject in klp_object statically allocated livepatch: Prevent patch inconsistencies if the coming module notifier fails livepatch: match return value to function signature x86: kaslr: fix build due to missing ALIGN definition livepatch: x86: make kASLR logic more accurate x86: introduce kaslr_offset()
2015-06-03x86/mm: Decouple <linux/vmalloc.h> from <asm/io.h>Stephen Rothwell1-0/+1
Nothing in <asm/io.h> uses anything from <linux/vmalloc.h>, so remove it from there and fix up the resulting build problems triggered on x86 {64|32}-bit {def|allmod|allno}configs. The breakages were triggering in places where x86 builds relied on vmalloc() facilities but did not include <linux/vmalloc.h> explicitly and relied on the implicit inclusion via <asm/io.h>. Also add: - <linux/init.h> to <linux/io.h> - <asm/pgtable_types> to <asm/io.h> ... which were two other implicit header file dependencies. Suggested-by: David Miller <davem@davemloft.net> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> [ Tidied up the changelog. ] Acked-by: David Miller <davem@davemloft.net> Acked-by: Takashi Iwai <tiwai@suse.de> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Vinod Koul <vinod.koul@intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Colin Cross <ccross@android.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: James E.J. Bottomley <JBottomley@odin.com> Cc: Jaroslav Kysela <perex@perex.cz> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Kees Cook <keescook@chromium.org> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Kristen Carlson Accardi <kristen@linux.intel.com> Cc: Len Brown <lenb@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: Suma Ramars <sramars@cisco.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-29x86: introduce kaslr_offset()Jiri Kosina1-1/+2
Offset that has been chosen for kaslr during kernel decompression can be easily computed as a difference between _text and __START_KERNEL. We are already making use of this in dump_kernel_offset() notifier and in arch_crash_save_vmcoreinfo(). Introduce kaslr_offset() that makes this computation instead of hard-coding it, so that other kernel code (such as live patching) can make use of it. Also convert existing users to make use of it. This patch is equivalent transofrmation without any effects on the resulting code: $ diff -u vmlinux.old.asm vmlinux.new.asm --- vmlinux.old.asm 2015-04-28 17:55:19.520983368 +0200 +++ vmlinux.new.asm 2015-04-28 17:55:24.141206072 +0200 @@ -1,5 +1,5 @@ -vmlinux.old: file format elf64-x86-64 +vmlinux.new: file format elf64-x86-64 Disassembly of section .text: $ Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2014-12-16x86, irq: Move IOAPIC related declarations from hw_irq.h into io_apic.hJiang Liu1-0/+1
Clean up code by moving IOAPIC related declarations from hw_irq.h into io_apic.h. Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Grant Likely <grant.likely@linaro.org> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Matt Fleming <matt.fleming@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Christian Gmeiner <christian.gmeiner@gmail.com> Cc: Aubrey <aubrey.li@linux.intel.com> Cc: Ryan Desfosses <ryan@desfo.org> Cc: Quentin Lambert <lambert.quentin@gmail.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: http://lkml.kernel.org/r/1414397531-28254-14-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-08-29kexec: create a new config option CONFIG_KEXEC_FILE for new syscallVivek Goyal1-0/+11
Currently new system call kexec_file_load() and all the associated code compiles if CONFIG_KEXEC=y. But new syscall also compiles purgatory code which currently uses gcc option -mcmodel=large. This option seems to be available only gcc 4.4 onwards. Hiding new functionality behind a new config option will not break existing users of old gcc. Those who wish to enable new functionality will require new gcc. Having said that, I am trying to figure out how can I move away from using -mcmodel=large but that can take a while. I think there are other advantages of introducing this new config option. As this option will be enabled only on x86_64, other arches don't have to compile generic kexec code which will never be used. This new code selects CRYPTO=y and CRYPTO_SHA256=y. And all other arches had to do this for CONFIG_KEXEC. Now with introduction of new config option, we can remove crypto dependency from other arches. Now CONFIG_KEXEC_FILE is available only on x86_64. So whereever I had CONFIG_X86_64 defined, I got rid of that. For CONFIG_KEXEC_FILE, instead of doing select CRYPTO=y, I changed it to "depends on CRYPTO=y". This should be safer as "select" is not recursive. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: H. Peter Anvin <hpa@zytor.com> Tested-by: Shaun Ruffell <sruffell@digium.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08kexec: verify the signature of signed PE bzImageVivek Goyal1-0/+11
This is the final piece of the puzzle of verifying kernel image signature during kexec_file_load() syscall. This patch calls into PE file routines to verify signature of bzImage. If signature are valid, kexec_file_load() succeeds otherwise it fails. Two new config options have been introduced. First one is CONFIG_KEXEC_VERIFY_SIG. This option enforces that kernel has to be validly signed otherwise kernel load will fail. If this option is not set, no signature verification will be done. Only exception will be when secureboot is enabled. In that case signature verification should be automatically enforced when secureboot is enabled. But that will happen when secureboot patches are merged. Second config option is CONFIG_KEXEC_BZIMAGE_VERIFY_SIG. This option enables signature verification support on bzImage. If this option is not set and previous one is set, kernel image loading will fail because kernel does not have support to verify signature of bzImage. I tested these patches with both "pesign" and "sbsign" signed bzImages. I used signing_key.priv key and signing_key.x509 cert for signing as generated during kernel build process (if module signing is enabled). Used following method to sign bzImage. pesign ====== - Convert DER format cert to PEM format cert openssl x509 -in signing_key.x509 -inform DER -out signing_key.x509.PEM -outform PEM - Generate a .p12 file from existing cert and private key file openssl pkcs12 -export -out kernel-key.p12 -inkey signing_key.priv -in signing_key.x509.PEM - Import .p12 file into pesign db pk12util -i /tmp/kernel-key.p12 -d /etc/pki/pesign - Sign bzImage pesign -i /boot/vmlinuz-3.16.0-rc3+ -o /boot/vmlinuz-3.16.0-rc3+.signed.pesign -c "Glacier signing key - Magrathea" -s sbsign ====== sbsign --key signing_key.priv --cert signing_key.x509.PEM --output /boot/vmlinuz-3.16.0-rc3+.signed.sbsign /boot/vmlinuz-3.16.0-rc3+ Patch details: Well all the hard work is done in previous patches. Now bzImage loader has just call into that code and verify whether bzImage signature are valid or not. Also create two config options. First one is CONFIG_KEXEC_VERIFY_SIG. This option enforces that kernel has to be validly signed otherwise kernel load will fail. If this option is not set, no signature verification will be done. Only exception will be when secureboot is enabled. In that case signature verification should be automatically enforced when secureboot is enabled. But that will happen when secureboot patches are merged. Second config option is CONFIG_KEXEC_BZIMAGE_VERIFY_SIG. This option enables signature verification support on bzImage. If this option is not set and previous one is set, kernel image loading will fail because kernel does not have support to verify signature of bzImage. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Cc: Borislav Petkov <bp@suse.de> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Greg Kroah-Hartman <greg@kroah.com> Cc: Dave Young <dyoung@redhat.com> Cc: WANG Chao <chaowang@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Matt Fleming <matt@console-pimps.org> Cc: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08kexec: support for kexec on panic using new system callVivek Goyal1-0/+40
This patch adds support for loading a kexec on panic (kdump) kernel usning new system call. It prepares ELF headers for memory areas to be dumped and for saved cpu registers. Also prepares the memory map for second kernel and limits its boot to reserved areas only. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Cc: Borislav Petkov <bp@suse.de> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Greg Kroah-Hartman <greg@kroah.com> Cc: Dave Young <dyoung@redhat.com> Cc: WANG Chao <chaowang@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08kexec-bzImage64: support for loading bzImage using 64bit entryVivek Goyal1-2/+3
This is loader specific code which can load bzImage and set it up for 64bit entry. This does not take care of 32bit entry or real mode entry. 32bit mode entry can be implemented if somebody needs it. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Cc: Borislav Petkov <bp@suse.de> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Greg Kroah-Hartman <greg@kroah.com> Cc: Dave Young <dyoung@redhat.com> Cc: WANG Chao <chaowang@redhat.com> Cc: Baoquan He <bhe@redhat.com>