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2014-10-14kexec: remove the unused function parameterBaoquan He
This is a cleanup. In function parse_crashkernel_suffix, the parameter crash_base is not used. So here remove it. Signed-off-by: Baoquan He <bhe@redhat.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-14kexec: take the segment adding out of locate_mem_hole functionsBaoquan He
In locate_mem_hole functions, a memory hole is located and added as kexec_segment. But from the name of locate_mem_hole, it should only take responsibility of searching a available memory hole to contain data of a specified size. So in this patch add a new field 'mem' into kexec_buf, then take that kexec segment adding code out of locate_mem_hole_top_down and locate_mem_hole_bottom_up. This make clear of the functionality of locate_mem_hole just like it declars to do. And by this locate_mem_hole_callback chould be used later if anyone want to locate a memory hole for other use. Meanwhile Vivek suggested opening code function __kexec_add_segment(), that way we have to retreive ksegment pointer once and it is easy to read. So just do it in this patch and remove __kexec_add_segment() since no one use it anymore. Signed-off-by: Baoquan He <bhe@redhat.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-29kexec: create a new config option CONFIG_KEXEC_FILE for new syscallVivek Goyal
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 Goyal
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 Goyal
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 Goyal
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> 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: load and relocate purgatory at kernel load timeVivek Goyal
Load purgatory code in RAM and relocate it based on the location. Relocation code has been inspired by module relocation code and purgatory relocation code in kexec-tools. Also compute the checksums of loaded kexec segments and store them in purgatory. Arch independent code provides this functionality so that arch dependent bootloaders can make use of it. Helper functions are provided to get/set symbol values in purgatory which are used by bootloaders later to set things like stack and entry point of second kernel etc. 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: implementation of new syscall kexec_file_loadVivek Goyal
Previous patch provided the interface definition and this patch prvides implementation of new syscall. Previously segment list was prepared in user space. Now user space just passes kernel fd, initrd fd and command line and kernel will create a segment list internally. This patch contains generic part of the code. Actual segment preparation and loading is done by arch and image specific loader. Which comes in next patch. [akpm@linux-foundation.org: coding-style fixes] 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: new syscall kexec_file_load() declarationVivek Goyal
This is the new syscall kexec_file_load() declaration/interface. I have reserved the syscall number only for x86_64 so far. Other architectures (including i386) can reserve syscall number when they enable the support for this new syscall. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Borislav Petkov <bp@suse.de> 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: use common function for kimage_normal_alloc() and kimage_crash_alloc()Vivek Goyal
kimage_normal_alloc() and kimage_crash_alloc() are doing lot of similar things and differ only little. So instead of having two separate functions create a common function kimage_alloc_init() and pass it the "flags" argument which tells whether it is normal kexec or kexec_on_panic. And this function should be able to deal with both the cases. This consolidation also helps later where we can use a common function kimage_file_alloc_init() to handle normal and crash cases for new file based kexec syscall. 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: move segment verification code in a separate functionVivek Goyal
Previously do_kimage_alloc() will allocate a kimage structure, copy segment list from user space and then do the segment list sanity verification. Break down this function in 3 parts. do_kimage_alloc_init() to do actual allocation and basic initialization of kimage structure. copy_user_segment_list() to copy segment list from user space and sanity_check_segment_list() to verify the sanity of segment list as passed by user space. In later patches, I need to only allocate kimage and not copy segment list from user space. So breaking down in smaller functions enables re-use of code at other places. 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: rename unusebale_pages to unusable_pagesVivek Goyal
Let's use the more common "unusable". This patch was originally written and posted by Boris. I am including it in this patch series. Signed-off-by: Borislav Petkov <bp@suse.de> 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>
2014-07-30kexec: fix build error when hugetlbfs is disabledDavid Rientjes
free_huge_page() is undefined without CONFIG_HUGETLBFS and there's no need to filter PageHuge() page is such a configuration either, so avoid exporting the symbol to fix a build error: In file included from kernel/kexec.c:14:0: kernel/kexec.c: In function 'crash_save_vmcoreinfo_init': kernel/kexec.c:1623:20: error: 'free_huge_page' undeclared (first use in this function) VMCOREINFO_SYMBOL(free_huge_page); ^ Introduced by commit 8f1d26d0e59b ("kexec: export free_huge_page to VMCOREINFO") Reported-by: kbuild test robot <fengguang.wu@intel.com> Acked-by: Olof Johansson <olof@lixom.net> Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp> Cc: Baoquan He <bhe@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-07-30kexec: export free_huge_page to VMCOREINFOAtsushi Kumagai
PG_head_mask was added into VMCOREINFO to filter huge pages in b3acc56bfe1 ("kexec: save PG_head_mask in VMCOREINFO"), but makedumpfile still need another symbol to filter *hugetlbfs* pages. If a user hope to filter user pages, makedumpfile tries to exclude them by checking the condition whether the page is anonymous, but hugetlbfs pages aren't anonymous while they also be user pages. We know it's possible to detect them in the same way as PageHuge(), so we need the start address of free_huge_page(): int PageHuge(struct page *page) { if (!PageCompound(page)) return 0; page = compound_head(page); return get_compound_page_dtor(page) == free_huge_page; } For that reason, this patch changes free_huge_page() into public to export it to VMCOREINFO. Signed-off-by: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp> Acked-by: Baoquan He <bhe@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>
2014-06-23kexec: save PG_head_mask in VMCOREINFOPetr Tesarik
To allow filtering of huge pages, makedumpfile must be able to identify them in the dump. This can be done by checking the appropriate page flag, so communicate its value to makedumpfile through the VMCOREINFO interface. There's only one small catch. Depending on how many page flags are available on a given architecture, this bit can be called PG_head or PG_compound. I sent a similar patch back in 2012, but Eric Biederman did not like using an #ifdef. So, this time I'm adding a common symbol (PG_head_mask) instead. See https://lkml.org/lkml/2012/11/28/91 for the previous version. Signed-off-by: Petr Tesarik <ptesarik@suse.cz> Acked-by: Vivek Goyal <vgoyal@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Shaohua Li <shli@kernel.org> Cc: Alexey Kardashevskiy <aik@ozlabs.ru> Cc: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-06kernel/kexec.c: convert printk to pr_foo()Fabian Frederick
+ some pr_warning -> pr_warn and checkpatch warning fixes Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Eric Biederman <ebiederm@xmission.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>
2014-05-28powerpc, kexec: Fix "Processor X is stuck" issue during kexec from ST modeSrivatsa S. Bhat
If we try to perform a kexec when the machine is in ST (Single-Threaded) mode (ppc64_cpu --smt=off), the kexec operation doesn't succeed properly, and we get the following messages during boot: [ 0.089866] POWER8 performance monitor hardware support registered [ 0.089985] power8-pmu: PMAO restore workaround active. [ 5.095419] Processor 1 is stuck. [ 10.097933] Processor 2 is stuck. [ 15.100480] Processor 3 is stuck. [ 20.102982] Processor 4 is stuck. [ 25.105489] Processor 5 is stuck. [ 30.108005] Processor 6 is stuck. [ 35.110518] Processor 7 is stuck. [ 40.113369] Processor 9 is stuck. [ 45.115879] Processor 10 is stuck. [ 50.118389] Processor 11 is stuck. [ 55.120904] Processor 12 is stuck. [ 60.123425] Processor 13 is stuck. [ 65.125970] Processor 14 is stuck. [ 70.128495] Processor 15 is stuck. [ 75.131316] Processor 17 is stuck. Note that only the sibling threads are stuck, while the primary threads (0, 8, 16 etc) boot just fine. Looking closer at the previous step of kexec, we observe that kexec tries to wakeup (bring online) the sibling threads of all the cores, before performing kexec: [ 9464.131231] Starting new kernel [ 9464.148507] kexec: Waking offline cpu 1. [ 9464.148552] kexec: Waking offline cpu 2. [ 9464.148600] kexec: Waking offline cpu 3. [ 9464.148636] kexec: Waking offline cpu 4. [ 9464.148671] kexec: Waking offline cpu 5. [ 9464.148708] kexec: Waking offline cpu 6. [ 9464.148743] kexec: Waking offline cpu 7. [ 9464.148779] kexec: Waking offline cpu 9. [ 9464.148815] kexec: Waking offline cpu 10. [ 9464.148851] kexec: Waking offline cpu 11. [ 9464.148887] kexec: Waking offline cpu 12. [ 9464.148922] kexec: Waking offline cpu 13. [ 9464.148958] kexec: Waking offline cpu 14. [ 9464.148994] kexec: Waking offline cpu 15. [ 9464.149030] kexec: Waking offline cpu 17. Instrumenting this piece of code revealed that the cpu_up() operation actually fails with -EBUSY. Thus, only the primary threads of all the cores are online during kexec, and hence this is a sure-shot receipe for disaster, as explained in commit e8e5c2155b (powerpc/kexec: Fix orphaned offline CPUs across kexec), as well as in the comment above wake_offline_cpus(). It turns out that cpu_up() was returning -EBUSY because the variable 'cpu_hotplug_disabled' was set to 1; and this disabling of CPU hotplug was done by migrate_to_reboot_cpu() inside kernel_kexec(). Now, migrate_to_reboot_cpu() was originally written with the assumption that any further code will not need to perform CPU hotplug, since we are anyway in the reboot path. However, kexec is clearly not such a case, since we depend on onlining CPUs, atleast on powerpc. So re-enable cpu-hotplug after returning from migrate_to_reboot_cpu() in the kexec path, to fix this regression in kexec on powerpc. Also, wrap the cpu_up() in powerpc kexec code within a WARN_ON(), so that we can catch such issues more easily in the future. Fixes: c97102ba963 (kexec: migrate to reboot cpu) Cc: stable@vger.kernel.org Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-04-07kernel: use macros from compiler.h instead of __attribute__((...))Gideon Israel Dsouza
To increase compiler portability there is <linux/compiler.h> which provides convenience macros for various gcc constructs. Eg: __weak for __attribute__((weak)). I've replaced all instances of gcc attributes with the right macro in the kernel subsystem. Signed-off-by: Gideon Israel Dsouza <gidisrael@gmail.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03kernel: audit/fix non-modular users of module_init in core codePaul Gortmaker
Code that is obj-y (always built-in) or dependent on a bool Kconfig (built-in or absent) can never be modular. So using module_init as an alias for __initcall can be somewhat misleading. Fix these up now, so that we can relocate module_init from init.h into module.h in the future. If we don't do this, we'd have to add module.h to obviously non-modular code, and that would be a worse thing. The audit targets the following module_init users for change: kernel/user.c obj-y kernel/kexec.c bool KEXEC (one instance per arch) kernel/profile.c bool PROFILING kernel/hung_task.c bool DETECT_HUNG_TASK kernel/sched/stats.c bool SCHEDSTATS kernel/user_namespace.c bool USER_NS Note that direct use of __initcall is discouraged, vs. one of the priority categorized subgroups. As __initcall gets mapped onto device_initcall, our use of subsys_initcall (which makes sense for these files) will thus change this registration from level 6-device to level 4-subsys (i.e. slightly earlier). However no observable impact of that difference has been observed during testing. Also, two instances of missing ";" at EOL are fixed in kexec. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Eric Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-03-06kexec/compat: convert to COMPAT_SYSCALL_DEFINE with changing parameter typesHeiko Carstens
In order to allow the COMPAT_SYSCALL_DEFINE macro generate code that performs proper zero and sign extension convert all 64 bit parameters to their corresponding 32 bit compat counterparts. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-01-27kernel/kexec.c: use vscnprintf() instead of vsnprintf() in ↵Chen Gang
vmcoreinfo_append_str() vsnprintf() may let 'r' larger than sizeof(buf), in this case, if 'r' is also less than "vmcoreinfo_max_size - vmcoreinfo_size" (left size of destination buffer), next memcpy() will read the unexpected addresses. Signed-off-by: Chen Gang <gang.chen@asianux.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-23kexec: add sysctl to disable kexec_loadKees Cook
For general-purpose (i.e. distro) kernel builds it makes sense to build with CONFIG_KEXEC to allow end users to choose what kind of things they want to do with kexec. However, in the face of trying to lock down a system with such a kernel, there needs to be a way to disable kexec_load (much like module loading can be disabled). Without this, it is too easy for the root user to modify kernel memory even when CONFIG_STRICT_DEVMEM and modules_disabled are set. With this change, it is still possible to load an image for use later, then disable kexec_load so the image (or lack of image) can't be altered. The intention is for using this in environments where "perfect" enforcement is hard. Without a verified boot, along with verified modules, and along with verified kexec, this is trying to give a system a better chance to defend itself (or at least grow the window of discoverability) against attack in the face of a privilege escalation. In my mind, I consider several boot scenarios: 1) Verified boot of read-only verified root fs loading fd-based verification of kexec images. 2) Secure boot of writable root fs loading signed kexec images. 3) Regular boot loading kexec (e.g. kcrash) image early and locking it. 4) Regular boot with no control of kexec image at all. 1 and 2 don't exist yet, but will soon once the verified kexec series has landed. 4 is the state of things now. The gap between 2 and 4 is too large, so this change creates scenario 3, a middle-ground above 4 when 2 and 1 are not possible for a system. Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Rik van Riel <riel@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-12-18kexec: migrate to reboot cpuVivek Goyal
Commit 1b3a5d02ee07 ("reboot: move arch/x86 reboot= handling to generic kernel") moved reboot= handling to generic code. In the process it also removed the code in native_machine_shutdown() which are moving reboot process to reboot_cpu/cpu0. I guess that thought must have been that all reboot paths are calling migrate_to_reboot_cpu(), so we don't need this special handling. But kexec reboot path (kernel_kexec()) is not calling migrate_to_reboot_cpu() so above change broke kexec. Now reboot can happen on non-boot cpu and when INIT is sent in second kerneo to bring up BP, it brings down the machine. So start calling migrate_to_reboot_cpu() in kexec reboot path to avoid this problem. Bisected by WANG Chao. Reported-by: Matthew Whitehead <mwhitehe@redhat.com> Reported-by: Dave Young <dyoung@redhat.com> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Tested-by: Baoquan He <bhe@redhat.com> Tested-by: WANG Chao <chaowang@redhat.com> Acked-by: H. Peter Anvin <hpa@linux.intel.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-12-07PCI: Disable Bus Master only on kexec rebootKhalid Aziz
Add a flag to tell the PCI subsystem that kernel is shutting down in preparation to kexec a kernel. Add code in PCI subsystem to use this flag to clear Bus Master bit on PCI devices only in case of kexec reboot. This fixes a power-off problem on Acer Aspire V5-573G and likely other machines and avoids any other issues caused by clearing Bus Master bit on PCI devices in normal shutdown path. The problem was introduced by b566a22c2332 ("PCI: disable Bus Master on PCI device shutdown"). This patch is based on discussion at http://marc.info/?l=linux-pci&m=138425645204355&w=2 Link: https://bugzilla.kernel.org/show_bug.cgi?id=63861 Reported-by: Chang Liu <cl91tp@gmail.com> Signed-off-by: Khalid Aziz <khalid.aziz@oracle.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Konstantin Khlebnikov <koct9i@gmail.com> Cc: stable@vger.kernel.org # v3.5+
2013-11-15Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree updates from Jiri Kosina: "Usual earth-shaking, news-breaking, rocket science pile from trivial.git" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits) doc: usb: Fix typo in Documentation/usb/gadget_configs.txt doc: add missing files to timers/00-INDEX timekeeping: Fix some trivial typos in comments mm: Fix some trivial typos in comments irq: Fix some trivial typos in comments NUMA: fix typos in Kconfig help text mm: update 00-INDEX doc: Documentation/DMA-attributes.txt fix typo DRM: comment: `halve' -> `half' Docs: Kconfig: `devlopers' -> `developers' doc: typo on word accounting in kprobes.c in mutliple architectures treewide: fix "usefull" typo treewide: fix "distingush" typo mm/Kconfig: Grammar s/an/a/ kexec: Typo s/the/then/ Documentation/kvm: Update cpuid documentation for steal time and pv eoi treewide: Fix common typo in "identify" __page_to_pfn: Fix typo in comment Correct some typos for word frequency clk: fixed-factor: Fix a trivial typo ...
2013-10-14kexec: Typo s/the/then/Geert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-09-11kexec: remove unnecessary returnXishi Qiu
Code can not run here forever, so remove the unnecessary return. Signed-off-by: Xishi Qiu <qiuxishi@huawei.com> Suggested-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Reviewed-by: Simon Horman <horms@verge.net.au> Reviewed-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30kexec: Use min() and min_t() to simplify logicZhang Yanfei
Simplify the logic of variable assignments. [akpm@linux-foundation.org: replace min_t with min, remove unneeded casts] Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Reviewed-by: Simon Horman <horms@verge.net.au> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30kexec: fix wrong types of some local variablesZhang Yanfei
The types of the following local variables: - ubytes/mbytes in kimage_load_crash_segment()/kimage_load_normal_segment() - r in vmcoreinfo_append_str() are wrong, so fix them. Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Simon Horman <horms@verge.net.au> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29kexec, vmalloc: export additional vmalloc layer informationAtsushi Kumagai
Now, vmap_area_list is exported as VMCOREINFO for makedumpfile to get the start address of vmalloc region (vmalloc_start). The address which contains vmalloc_start value is represented as below: vmap_area_list.next - OFFSET(vmap_area.list) + OFFSET(vmap_area.va_start) However, both OFFSET(vmap_area.va_start) and OFFSET(vmap_area.list) aren't exported as VMCOREINFO. So this patch exports them externally with small cleanup. [akpm@linux-foundation.org: vmalloc.h should include list.h for list_head] Signed-off-by: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp> Cc: Joonsoo Kim <js1304@gmail.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Dave Anderson <anderson@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ingo Molnar <mingo@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29mm, vmalloc: export vmap_area_list, instead of vmlistJoonsoo Kim
Although our intention is to unexport internal structure entirely, but there is one exception for kexec. kexec dumps address of vmlist and makedumpfile uses this information. We are about to remove vmlist, then another way to retrieve information of vmalloc layer is needed for makedumpfile. For this purpose, we export vmap_area_list, instead of vmlist. Signed-off-by: Joonsoo Kim <js1304@gmail.com> Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Dave Anderson <anderson@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29mm,kexec: use common help functions to free reserved pagesJiang Liu
Use common help functions to free reserved pages. Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: Eric Biederman <ebiederm@xmission.com> Reviewed-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-17kexec: use Crash kernel for Crash kernel lowYinghai Lu
We can extend kexec-tools to support multiple "Crash kernel" in /proc/iomem instead. So we can use "Crash kernel" instead of "Crash kernel low" in /proc/iomem. Suggested-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/1366089828-19692-3-git-send-email-yinghai@kernel.org Acked-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-04-17x86, kdump: Change crashkernel_high/low= to crashkernel=,high/lowYinghai Lu
Per hpa, use crashkernel=X,high crashkernel=Y,low instead of crashkernel_hign=X crashkernel_low=Y. As that could be extensible. -v2: according to Vivek, change delimiter to ; -v3: let hign and low only handle simple form and it conforms to description in kernel-parameters.txt still keep crashkernel=X override any crashkernel=X,high crashkernel=Y,low -v4: update get_last_crashkernel returning and add more strict checking in parse_crashkernel_simple() found by HATAYAMA. -v5: Change delimiter back to , according to HPA. also separate parse_suffix from parse_simper according to vivek. so we can avoid @pos in that path. -v6: Tight the checking about crashkernel=X,highblahblah,high found by HTYAYAMA. Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Signed-off-by: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/1366089828-19692-5-git-send-email-yinghai@kernel.org Acked-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-04-17x86, kdump: Retore crashkernel= to allocate under 896MYinghai Lu
Vivek found old kexec-tools does not work new kernel anymore. So change back crashkernel= back to old behavoir, and add crashkernel_high= to let user decide if buffer could be above 4G, and also new kexec-tools will be needed. -v2: let crashkernel=X override crashkernel_high= update description about _high will be ignored by crashkernel=X -v3: update description about kernel-parameters.txt according to Vivek. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/1366089828-19692-4-git-send-email-yinghai@kernel.org Acked-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-02-27kexec: avoid freeing NULL pointer in image_crash_alloc()Zhang Yanfei
Though there is no error if we free a NULL pointer, I think we could avoid this behaviour. Change the code a little in kimage_crash_alloc() could avoid this kind of unnecessary free. Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Sasha Levin <sasha.levin@oracle.com> Reviewed-by: Simon Horman <horms@verge.net.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27kexec: fix memory leak in function kimage_normal_allocZhang Yanfei
If kimage_normal_alloc() fails to alloc pages for image->swap_page, it should call kimage_free_page_list() to free allocated pages in image->control_pages list before it frees image. Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Sasha Levin <sasha.levin@oracle.com> Reviewed-by: Simon Horman <horms@verge.net.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27kexec: prevent double free on image allocation failureSasha Levin
If kimage_normal_alloc() fails to initialize an allocated kimage, it will free the image but would still set 'rimage', as a result kexec_load will try to free it again. This would explode as part of the freeing process is accessing internal members which point to uninitialized memory. Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27kexec: export PG_hwpoison flag into vmcoreinfoMitsuhiro Tanino
This patch exports a PG_hwpoison into vmcoreinfo when CONFIG_MEMORY_FAILURE is defined. "makedumpfile" needs to read information of memory, such as 'mem_section', 'zone', 'pageflags' from vmcore. We introduce a function into "makedumpfile" to exclude hwpoison page from vmcore dump. In order to introduce this function, PG_hwpoison flag have to export into vmcoreinfo. Signed-off-by: Mitsuhiro Tanino <mitsuhiro.tanino.gm@hitachi.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Mitsuhiro Tanino <mitsuhiro.tanino.gm@hitachi.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>
2013-02-27kexec: get rid of duplicate check for hole_endZhang Yanfei
hole_end has been checked to make sure it is <= crash_res.end in the while condition check, so the if condition check is duplicate. Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27kexec: add the values related to buddy system for filtering free pages.Atsushi Kumagai
tAdd adds the values related to buddy system to vmcoreinfo data so that makedumpfile (dump filtering command) can filter out all free pages with the new logic. It's faster than the current logic because it can distinguish free page by analyzing page structure at the same time as filtering for other unnecessary pages (e.g. anonymous page). OTOH, the current logic has to trace free_list to distinguish free pages while analyzing page structure to filter out other unnecessary pages. The new logic uses the fact that buddy page is marked by _mapcount == PAGE_BUDDY_MAPCOUNT_VALUE. But, _mapcount shares its memory with other fields for SLAB/SLUB when PG_slab is set, so we need to check if PG_slab is set or not before looking up _mapcount value. And we can get the order of buddy system from private field. To sum it up, the values below are required for this logic. Required values: - OFFSET(page._mapcount) - OFFSET(page.private) - NUMBER(PG_slab) - NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE) Changelog from v1 to v2: 1. remove SIZE(pageflags) The new logic was changed after I sent v1 patch. Accordingly, SIZE(pageflags) has been unnecessary for makedumpfile. What's makedumpfile: makedumpfile creates a small dumpfile by excluding unnecessary pages for the analysis. To distinguish unnecessary pages, makedumpfile gets the vmcoreinfo data which has the minimum debugging information only for dump filtering. Signed-off-by: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-29x86: Add Crash kernel low reservationYinghai Lu
During kdump kernel's booting stage, it need to find low ram for swiotlb buffer when system does not support intel iommu/dmar remapping. kexed-tools is appending memmap=exactmap and range from /proc/iomem with "Crash kernel", and that range is above 4G for 64bit after boot protocol 2.12. We need to add another range in /proc/iomem like "Crash kernel low", so kexec-tools could find that info and append to kdump kernel command line. Try to reserve some under 4G if the normal "Crash kernel" is above 4G. User could specify the size with crashkernel_low=XX[KMG]. -v2: fix warning that is found by Fengguang's test robot. -v3: move out get_mem_size change to another patch, to solve compiling warning that is found by Borislav Petkov <bp@alien8.de> -v4: user must specify crashkernel_low if system does not support intel or amd iommu. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/1359058816-7615-31-git-send-email-yinghai@kernel.org Cc: Eric Biederman <ebiederm@xmission.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-10-06kdump: remove unneeded includeWei Yongjun
The inclusion of <generated/utsrelease.h> is unnecessary. Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Reviewed-by: Simon Horman <horms@verge.net.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-30kdump: append newline to the last lien of vmcoreinfo noteVivek Goyal
The last line of vmcoreinfo note does not end with \n. Parsing all the lines in note becomes easier if all lines end with \n instead of trying to special case the last line. I know at least one tool, vmcore-dmesg in kexec-tools tree which made the assumption that all lines end with \n. I think it is a good idea to fix it. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-28Merge branch 'akpm' (Andrew's patch-bomb)Linus Torvalds
Merge third batch of patches from Andrew Morton: - Some MM stragglers - core SMP library cleanups (on_each_cpu_mask) - Some IPI optimisations - kexec - kdump - IPMI - the radix-tree iterator work - various other misc bits. "That'll do for -rc1. I still have ~10 patches for 3.4, will send those along when they've baked a little more." * emailed from Andrew Morton <akpm@linux-foundation.org>: (35 commits) backlight: fix typo in tosa_lcd.c crc32: add help text for the algorithm select option mm: move hugepage test examples to tools/testing/selftests/vm mm: move slabinfo.c to tools/vm mm: move page-types.c from Documentation to tools/vm selftests/Makefile: make `run_tests' depend on `all' selftests: launch individual selftests from the main Makefile radix-tree: use iterators in find_get_pages* functions radix-tree: rewrite gang lookup using iterator radix-tree: introduce bit-optimized iterator fs/proc/namespaces.c: prevent crash when ns_entries[] is empty nbd: rename the nbd_device variable from lo to nbd pidns: add reboot_pid_ns() to handle the reboot syscall sysctl: use bitmap library functions ipmi: use locks on watchdog timeout set on reboot ipmi: simplify locking ipmi: fix message handling during panics ipmi: use a tasklet for handling received messages ipmi: increase KCS timeouts ipmi: decrease the IPMI message transaction time in interrupt mode ...
2012-03-28kexec: add further check to crashkernelZhenzhong Duan
When using crashkernel=2M-256M, the kernel doesn't give any warning. This is misleading sometimes. Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-28kexec: crash: don't save swapper_pg_dir for !CONFIG_MMU configurationsWill Deacon
nommu platforms don't have very interesting swapper_pg_dir pointers and usually just #define them to NULL, meaning that we can't include them in the vmcoreinfo on the kexec crash path. This patch only saves the swapper_pg_dir if we have an MMU. Signed-off-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Simon Horman <horms@verge.net.au> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-28Remove all #inclusions of asm/system.hDavid Howells
Remove all #inclusions of asm/system.h preparatory to splitting and killing it. Performed with the following command: perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *` Signed-off-by: David Howells <dhowells@redhat.com>
2012-01-29PM / Sleep: Introduce "late suspend" and "early resume" of devicesRafael J. Wysocki
The current device suspend/resume phases during system-wide power transitions appear to be insufficient for some platforms that want to use the same callback routines for saving device states and related operations during runtime suspend/resume as well as during system suspend/resume. In principle, they could point their .suspend_noirq() and .resume_noirq() to the same callback routines as their .runtime_suspend() and .runtime_resume(), respectively, but at least some of them require device interrupts to be enabled while the code in those routines is running. It also makes sense to have device suspend-resume callbacks that will be executed with runtime PM disabled and with device interrupts enabled in case someone needs to run some special code in that context during system-wide power transitions. Apart from this, .suspend_noirq() and .resume_noirq() were introduced as a workaround for drivers using shared interrupts and failing to prevent their interrupt handlers from accessing suspended hardware. It appears to be better not to use them for other porposes, or we may have to deal with some serious confusion (which seems to be happening already). For the above reasons, introduce new device suspend/resume phases, "late suspend" and "early resume" (and analogously for hibernation) whose callback will be executed with runtime PM disabled and with device interrupts enabled and whose callback pointers generally may point to runtime suspend/resume routines. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Reviewed-by: Kevin Hilman <khilman@ti.com>
2012-01-12kdump: crashk_res init check for /sys/kernel/kexec_crash_sizeMichael Holzheu
Currently it is possible to set the crash_size via the sysfs /sys/kernel/kexec_crash_size even if no crash kernel memory has been defined with the "crashkernel" parameter. In this case "crashk_res" is not initialized and crashk_res.start = crashk_res.end = 0. Unfortunately resource_size(&crashk_res) returns 1 in this case. This breaks the s390 implementation of crash_(un)map_reserved_pages(). To fix the problem the correct "old_size" is now calculated in crash_shrink_memory(). "old_size is set to "0" if crashk_res is not initialized. With this change crash_shrink_memory() will do nothing, when "crashk_res" is not initialized. It will return "0" for "echo 0 > /sys/kernel/kexec_crash_size" and -EINVAL for "echo [not zero] > /sys/kernel/kexec_crash_size". In addition to that this patch also simplifies the "ret = -EINVAL" vs. "ret = 0" logic as suggested by Simon Horman. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Reviewed-by: Dave Young <dyoung@redhat.com> Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com> Reviewed-by: Simon Horman <horms@verge.net.au> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>