BMC/Intel-BMC/linux.git/arch/x86/kernel/machine_kexec_32.c, branch dev-4.18

x86/kexec: Avoid double free_page() upon do_kexec_load() failure

2018-05-13T17:50:06+00:00

>From ff82bedd3e12f0d3353282054ae48c3bd8c72012 Mon Sep 17 00:00:00 2001 From: Tetsuo Handa 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 Signed-off-by: Tetsuo Handa Signed-off-by: Thomas Gleixner Acked-by: Baoquan He Cc: thomas.lendacky@amd.com Cc: prudo@linux.vnet.ibm.com Cc: Huang Ying Cc: syzkaller-bugs@googlegroups.com Cc: takahiro.akashi@linaro.org Cc: H. Peter Anvin 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

x86/apic: Remove the (now) unused disable_IO_APIC() function

2018-02-17T10:47:45+00:00

No one uses it anymore. Signed-off-by: Baoquan He Reviewed-by: Eric W. Biederman Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner 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

x86/apic: Split disable_IO_APIC() into two functions to fix CONFIG_KEXEC_JUMP=y

2018-02-17T10:47:44+00:00

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 Reviewed-by: Eric W. Biederman Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner 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

x86-32: Fix kexec with stack canary (CONFIG_CC_STACKPROTECTOR)

2017-12-27T19:59:41+00:00

Commit e802a51ede91 ("x86/idt: Consolidate IDT invalidation") cleaned up and unified the IDT invalidation that existed in a couple of places. It changed no actual real code. Despite not changing any actual real code, it _did_ change code generation: by implementing the common idt_invalidate() function in archx86/kernel/idt.c, it made the use of the function in arch/x86/kernel/machine_kexec_32.c be a real function call rather than an (accidental) inlining of the function. That, in turn, exposed two issues: - in load_segments(), we had incorrectly reset all the segment registers, which then made the stack canary load (which gcc does using offset of %gs) cause a trap. Instead of %gs pointing to the stack canary, it will be the normal zero-based kernel segment, and the stack canary load will take a page fault at address 0x14. - to make this even harder to debug, we had invalidated the GDT just before calling idt_invalidate(), which meant that the fault happened with an invalid GDT, which in turn causes a triple fault and immediate reboot. Fix this by (a) not reloading the special segments in load_segments(). We currently don't do any percpu accesses (which would require %fs on x86-32) in this area, but there's no reason to think that we might not want to do them, and like %gs, it's pointless to break it. (b) doing idt_invalidate() before invalidating the GDT, to keep things at least _slightly_ more debuggable for a bit longer. Without a IDT, traps will not work. Without a GDT, traps also will not work, but neither will any segment loads etc. So in a very real sense, the GDT is even more core than the IDT. Fixes: e802a51ede91 ("x86/idt: Consolidate IDT invalidation") Reported-and-tested-by: Alexandru Chirvasitu Signed-off-by: Linus Torvalds Signed-off-by: Thomas Gleixner Cc: Denys Vlasenko Cc: Peter Zijlstra Cc: Brian Gerst Cc: Steven Rostedt Cc: Borislav Petkov Cc: Andy Lutomirski Cc: Josh Poimboeuf Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/alpine.LFD.2.21.1712271143180.8572@i7.lan

x86/idt: Consolidate IDT invalidation

2017-08-29T10:07:26+00:00

kexec and reboot have both code to invalidate IDT. Create a common function and use it. Signed-off-by: Thomas Gleixner Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Steven Rostedt Link: http://lkml.kernel.org/r/20170828064958.600953282@linutronix.de Signed-off-by: Ingo Molnar

x86: use set_memory.h header

2017-05-09T00:15:13+00:00

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 Acked-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

x86/kexec: Add 5-level paging support

2017-03-27T06:56:13+00:00

Handle additional page table level in the kexec code. Signed-off-by: Kirill A. Shutemov Acked-by: Thomas Gleixner Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnd Bergmann Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Michal Hocko Cc: Peter Zijlstra 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

x86, irq: Move IOAPIC related declarations from hw_irq.h into io_apic.h

2014-12-16T13:08:17+00:00

Clean up code by moving IOAPIC related declarations from hw_irq.h into io_apic.h. Signed-off-by: Jiang Liu Cc: Konrad Rzeszutek Wilk Cc: Tony Luck Cc: Joerg Roedel Cc: Greg Kroah-Hartman Cc: H. Peter Anvin Cc: Benjamin Herrenschmidt Cc: Rafael J. Wysocki Cc: Bjorn Helgaas Cc: Randy Dunlap Cc: Yinghai Lu Cc: Borislav Petkov Cc: Prarit Bhargava Cc: Grant Likely Cc: Vivek Goyal Cc: Baoquan He Cc: Matt Fleming Cc: Fenghua Yu Cc: Christian Gmeiner Cc: Aubrey Cc: Ryan Desfosses Cc: Quentin Lambert Cc: Rafael J. Wysocki Link: http://lkml.kernel.org/r/1414397531-28254-14-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner

x86: Axe the lightly-used cpu_has_pae

2014-09-11T21:30:01+00:00

cpu_has_pae is only referenced in one place: the X86_32 kexec code (in a file not even built on 64-bit). It hardly warrants its own macro, or the trouble we go to ensuring that it can't be called in X86_64 code. Axe the macro and replace it with a direct cpu feature check. Signed-off-by: Dave Hansen Link: http://lkml.kernel.org/r/20140911211511.AD76E774@viggo.jf.intel.com Acked-by: Borislav Petkov Signed-off-by: H. Peter Anvin

x86: Delete non-required instances of include

2014-01-07T05:25:18+00:00

None of these files are actually using any __init type directives and hence don't need to include . Most are just a left over from __devinit and __cpuinit removal, or simply due to code getting copied from one driver to the next. [ hpa: undid incorrect removal from arch/x86/kernel/head_32.S ] Signed-off-by: Paul Gortmaker Link: http://lkml.kernel.org/r/1389054026-12947-1-git-send-email-paul.gortmaker@windriver.com Signed-off-by: H. Peter Anvin