aboutsummaryrefslogtreecommitdiffstats
path: root/include/linux/kexec.h
Commit message (Collapse)AuthorAge
* kexec/i386: allocate page table pages dynamicallyHuang Ying2008-10-31
| | | | | | | | | | | | | | Impact: save .text size when kexec is built in but not loaded This patch adds an architecture specific struct kimage_arch into struct kimage. The pointers to page table pages used by kexec are added to struct kimage_arch. The page tables pages are dynamically allocated in machine_kexec_prepare instead of statically from BSS segment. This will save up to 20k memory when kexec image is not loaded. Signed-off-by: Huang Ying <ying.huang@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* kexec jump: rename KEXEC_CONTROL_CODE_SIZE to KEXEC_CONTROL_PAGE_SIZEHuang Ying2008-08-15
| | | | | | | | | | | | | | | | | | Rename KEXEC_CONTROL_CODE_SIZE to KEXEC_CONTROL_PAGE_SIZE, because control page is used for not only code on some platform. For example in kexec jump, it is used for data and stack too. [akpm@linux-foundation.org: unbreak powerpc and arm, finish conversion] Signed-off-by: Huang Ying <ying.huang@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kdump: report actual value of VMCOREINFO_OSRELEASE in VMCOREINFOBernhard Walle2008-08-05
| | | | | | | | | | | | | | | | | | | | The current implementation reports the structure name as VMCOREINFO_OSRELEASE in VMCOREINFO, e.g. VMCOREINFO_OSRELEASE=init_uts_ns.name.release That doesn't make sense because it's always the same. Instead, use the value, e.g. VMCOREINFO_OSRELEASE=2.6.26-rc3 That's also what the 'makedumpfile -g' does. Signed-off-by: Bernhard Walle <bwalle@suse.de> Cc: "Ken'ichi Ohmichi" <oomichi@mxs.nes.nec.co.jp> 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>
* kexec jumpHuang Ying2008-07-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch provides an enhancement to kexec/kdump. It implements the following features: - Backup/restore memory used by the original kernel before/after kexec. - Save/restore CPU state before/after kexec. The features of this patch can be used as a general method to call program in physical mode (paging turning off). This can be used to call BIOS code under Linux. kexec-tools needs to be patched to support kexec jump. The patches and the precompiled kexec can be download from the following URL: source: http://khibernation.sourceforge.net/download/release_v10/kexec-tools/kexec-tools-src_git_kh10.tar.bz2 patches: http://khibernation.sourceforge.net/download/release_v10/kexec-tools/kexec-tools-patches_git_kh10.tar.bz2 binary: http://khibernation.sourceforge.net/download/release_v10/kexec-tools/kexec_git_kh10 Usage example of calling some physical mode code and return: 1. Compile and install patched kernel with following options selected: CONFIG_X86_32=y CONFIG_KEXEC=y CONFIG_PM=y CONFIG_KEXEC_JUMP=y 2. Build patched kexec-tool or download the pre-built one. 3. Build some physical mode executable named such as "phy_mode" 4. Boot kernel compiled in step 1. 5. Load physical mode executable with /sbin/kexec. The shell command line can be as follow: /sbin/kexec --load-preserve-context --args-none phy_mode 6. Call physical mode executable with following shell command line: /sbin/kexec -e Implementation point: To support jumping without reserving memory. One shadow backup page (source page) is allocated for each page used by kexeced code image (destination page). When do kexec_load, the image of kexeced code is loaded into source pages, and before executing, the destination pages and the source pages are swapped, so the contents of destination pages are backupped. Before jumping to the kexeced code image and after jumping back to the original kernel, the destination pages and the source pages are swapped too. C ABI (calling convention) is used as communication protocol between kernel and called code. A flag named KEXEC_PRESERVE_CONTEXT for sys_kexec_load is added to indicate that the loaded kernel image is used for jumping back. Now, only the i386 architecture is supported. Signed-off-by: Huang Ying <ying.huang@intel.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Nigel Cunningham <nigel@nigel.suspend2.net> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vmcoreinfo: add "VMCOREINFO_" to all the call for vmcoreinfo_append_str()Ken'ichi Ohmichi2008-02-07
| | | | | | | | | | | | | | For readability, all the calls to vmcoreinfo_append_str() are changed to macros having a prefix "VMCOREINFO_". This discussion is the following: http://www.ussg.iu.edu/hypermail/linux/kernel/0709.3/0584.html Signed-off-by: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp> Acked-by: Simon Horman <horms@verge.net.au> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vmcoreinfo: use the existing offsetof() for VMCOREINFO_OFFSET()Ken'ichi Ohmichi2008-02-07
| | | | | | | | | | | | | It is better that the existing offsetof() is used for VMCOREINFO_OFFSET(). This discussion is the following: http://www.ussg.iu.edu/hypermail/linux/kernel/0709.3/0584.html Signed-off-by: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp> Acked-by: Simon Horman <horms@verge.net.au> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vmcoreinfo: rename vmcoreinfo's macros returning the sizeKen'ichi Ohmichi2008-02-07
| | | | | | | | | | | | | | | | | | | | | | | | This patchset is for the vmcoreinfo data. The vmcoreinfo data has the minimum debugging information only for dump filtering. makedumpfile (dump filtering command) gets it to distinguish unnecessary pages, and makedumpfile creates a small dumpfile. This patch: VMCOREINFO_SIZE() should be renamed VMCOREINFO_STRUCT_SIZE() since it's always returning the size of the struct with a given name. This change would allow VMCOREINFO_TYPEDEF_SIZE() to simply become VMCOREINFO_SIZE() since it need not be used exclusively for typedefs. This discussion is the following: http://www.ussg.iu.edu/hypermail/linux/kernel/0709.3/0582.html Signed-off-by: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp> Acked-by: David Rientjes <rientjes@google.com> Acked-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>
* Extended crashkernel command lineBernhard Walle2007-10-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds a extended crashkernel syntax that makes the value of reserved system RAM dependent on the system RAM itself: crashkernel=<range1>:<size1>[,<range2>:<size2>,...][@offset] range=start-[end] For example: crashkernel=512M-2G:64M,2G-:128M The motivation comes from distributors that configure their crashkernel command line automatically with some configuration tool (YaST, you know ;)). Of course that tool knows the value of System RAM, but if the user removes RAM, then the system becomes unbootable or at least unusable and error handling is very difficult. This series implements this change for i386, x86_64, ia64, ppc64 and sh. That should be all platforms that support kdump in current mainline. I tested all platforms except sh due to the lack of a sh processor. This patch: This is the generic part of the patch. It adds a parse_crashkernel() function in kernel/kexec.c that is called by the architecture specific code that actually reserves the memory. That function takes the whole command line and looks itself for "crashkernel=" in it. If there are multiple occurrences, then the last one is taken. The advantage is that if you have a bootloader like lilo or elilo which allows you to append a command line parameter but not to remove one (like in GRUB), then you can add another crashkernel value for testing at the boot command line and this one overwrites the command line in the configuration then. Signed-off-by: Bernhard Walle <bwalle@suse.de> Cc: Andi Kleen <ak@suse.de> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Vivek Goyal <vgoyal@in.ibm.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>
* add-vmcore: add a prefix "VMCOREINFO_" to the vmcoreinfo macrosKen'ichi Ohmichi2007-10-17
| | | | | | | | | | | | Add a prefix "VMCOREINFO_" to the vmcoreinfo macros. Old vmcoreinfo macros were defined as generic names SYMBOL/SIZE/OFFSET /LENGTH/CONFIG, and it is impossible to grep for them. So these names should be changed. This discussion is the following: http://www.ussg.iu.edu/hypermail/linux/kernel/0709.1/0415.html Signed-off-by: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* add-vmcore: add nodemask_t's size and NR_FREE_PAGES's value to vmcoreinfo_dataKen'ichi Ohmichi2007-10-17
| | | | | | | | | | | | | | [2/3] Add nodemask_t's size and NR_FREE_PAGES's value to vmcoreinfo_data. The dump filetering command 'makedumpfile'(v1.1.6 or before) had assumed the above values, and it was not good from the reliability viewpoint. So makedumpfile v1.2.0 came to need these values and I created the patch to let the kernel output them. makedumpfile site: https://sourceforge.net/projects/makedumpfile/ Signed-off-by: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* add-vmcore: cleanup the coding style according to Andrew's commentsKen'ichi Ohmichi2007-10-17
| | | | | | | | | | | | | | [1/3] Cleanup the coding style according to Andrew's comments: http://lists.infradead.org/pipermail/kexec/2007-August/000522.html - vmcoreinfo_append_str() should have suitable __attribute__s so that the compiler can check its use. - vmcoreinfo_max_size should have size_t. - Use get_seconds() instead of xtime.tv_sec. - Use init_uts_ns.name.release instead of UTS_RELEASE. Signed-off-by: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Add vmcoreinfoKen'ichi Ohmichi2007-10-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch set frees the restriction that makedumpfile users should install a vmlinux file (including the debugging information) into each system. makedumpfile command is the dump filtering feature for kdump. It creates a small dumpfile by filtering unnecessary pages for the analysis. To distinguish unnecessary pages, it needs a vmlinux file including the debugging information. These days, the debugging package becomes a huge file, and it is hard to install it into each system. To solve the problem, kdump developers discussed it at lkml and kexec-ml. As the result, we reached the conclusion that necessary information for dump filtering (called "vmcoreinfo") should be embedded into the first kernel file and it should be accessed through /proc/vmcore during the second kernel. (http://www.uwsg.iu.edu/hypermail/linux/kernel/0707.0/1806.html) Dan Aloni created the patch set for the above implementation. (http://www.uwsg.iu.edu/hypermail/linux/kernel/0707.1/1053.html) And I updated it for multi architectures and memory models. (http://lists.infradead.org/pipermail/kexec/2007-August/000479.html) Signed-off-by: Dan Aloni <da-x@monatomic.org> Signed-off-by: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp> Signed-off-by: Bernhard Walle <bwalle@suse.de> Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kdump/kexec: calculate note size at compile timeSimon Horman2007-05-08
| | | | | | | | | | | | | | | | | | | | | | | | | Currently the size of the per-cpu region reserved to save crash notes is set by the per-architecture value MAX_NOTE_BYTES. Which in turn is currently set to 1024 on all supported architectures. While testing ia64 I recently discovered that this value is in fact too small. The particular setup I was using actually needs 1172 bytes. This lead to very tedious failure mode where the tail of one elf note would overwrite the head of another if they ended up being alocated sequentially by kmalloc, which was often the case. It seems to me that a far better approach is to caclculate the size that the area needs to be. This patch does just that. If a simpler stop-gap patch for ia64 to be squeezed into 2.6.21(.X) is needed then this should be as easy as making MAX_NOTE_BYTES larger in arch/asm-ia64/kexec.h. Perhaps 2048 would be a good choice. However, I think that the approach in this patch is a much more robust idea. Acked-by: Vivek Goyal <vgoyal@in.ibm.com> Signed-off-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>
* [ARM] 4137/1: Add kexec supportRichard Purdie2007-02-16
| | | | | | | | | | | | | | | | Add kexec support to ARM. Improvements like commandline handling could be made but this patch gives basic functional support. It uses the next available syscall number, 347. Once the syscall number is known, userspace support will be finalised/submitted to kexec-tools, various patches already exist. Originally based on a patch by Maxim Syrchin but updated and forward ported by various people. Signed-off-by: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* Merge branch 'release' of ↵Linus Torvalds2006-12-07
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | master.kernel.org:/pub/scm/linux/kernel/git/aegl/linux-2.6 * 'release' of master.kernel.org:/pub/scm/linux/kernel/git/aegl/linux-2.6: [IA64] replace kmalloc+memset with kzalloc [IA64] resolve name clash by renaming is_available_memory() [IA64] Need export for csum_ipv6_magic [IA64] Fix DISCONTIGMEM without VIRTUAL_MEM_MAP [PATCH] Add support for type argument in PAL_GET_PSTATE [IA64] tidy up return value of ip_fast_csum [IA64] implement csum_ipv6_magic for ia64. [IA64] More Itanium PAL spec updates [IA64] Update processor_info features [IA64] Add se bit to Processor State Parameter structure [IA64] Add dp bit to cache and bus check structs [IA64] SN: Correctly update smp_affinty mask [IA64] sparse cleanups [IA64] IA64 Kexec/kdump
| * [IA64] IA64 Kexec/kdumpZou Nan hai2006-12-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Changes and updates. 1. Remove fake rendz path and related code according to discuss with Khalid Aziz. 2. fc.i offset fix in relocate_kernel.S. 3. iospic shutdown code eoi and mask race fix from Fujitsu. 4. Warm boot hook in machine_kexec to SN SAL code from Jack Steiner. 5. Send slave to SAL slave loop patch from Jay Lan. 6. Kdump on non-recoverable MCA event patch from Jay Lan 7. Use CTL_UNNUMBERED in kdump_on_init sysctl. Signed-off-by: Zou Nan hai <nanhai.zou@intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
* | [PATCH] Kexec / Kdump: Unify elf note codeMagnus Damm2006-12-07
|/ | | | | | | | | | | | | | | | | The elf note saving code is currently duplicated over several architectures. This cleanup patch simply adds code to a common file and then replaces the arch-specific code with calls to the newly added code. The only drawback with this approach is that s390 doesn't fully support kexec-on-panic which for that arch leads to introduction of unused code. Signed-off-by: Magnus Damm <magnus@valinux.co.jp> Cc: Vivek Goyal <vgoyal@in.ibm.com> Cc: Andi Kleen <ak@suse.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [MIPS] Add support for kexecNicolas Schichan2006-11-29
| | | | | | | | | A tiny userland application loading the kernel and invoking kexec_load for mips is available here: http://chac.le-poulpe.net/~nico/kexec/kexec-2006-10-18.tar.gz Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* [PATCH] Add a sysfs file to determine if a kexec kernel is loadedJeff Moyer2006-06-23
| | | | | | | | | | | | Create two files in /sys/kernel, kexec_loaded and kexec_crash_loaded. Each file contains a simple boolean value indicating whether the relevant kernel has been loaded into memory. The motivation for this is geared around support. Signed-off-by: Jeff Moyer <jmoyer@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] kexec: fix in free initrd when overlapped with crashkernel regionHaren Myneni2006-02-10
| | | | | | | | | | | | | | | | | | | | | | | It is possible that the reserved crashkernel region can be overlapped with initrd since the bootloader sets the initrd location. When the initrd region is freed, the second kernel memory will not be contiguous. The Kexec_load can cause an oops since there is no contiguous memory to write the second kernel or this memory could be used in the first kernel itself and may not be part of the dump. For example, on powerpc, the initrd is located at 36MB and the crashkernel starts at 32MB. The kexec_load caused panic since writing into non-allocated memory (after 36MB). We could see the similar issue even on other archs. One possibility is to move the initrd outside of crashkernel region. But, the initrd region will be freed anyway before the system is up. This patch fixes this issue and frees only regions that are not part of crashkernel memory in case overlaps. Signed-off-by: Haren Myneni <haren@us.ibm.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Vivek Goyal <vgoyal@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] sh: kexec() supportkogiidena2006-01-17
| | | | | | | | | | This adds kexec() support for SH. Signed-off-by: kogiidena <kogiidena@eggplant.ddo.jp> Signed-off-by: Paul Mundt <lethal@linux-sh.org> Cc: <fastboot@lists.osdl.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] kexec: increase max segment limitakpm@osdl.org2006-01-10
| | | | | | | | | | | | | | | ) From: Vivek Goyal <vgoyal@in.ibm.com> - In some cases, the number of segments, on a kexec load, exceeds the existing cap of 8. This patch increases the KEXEC_SEGMENT_MAX limit from 8 to 16. Signed-off-by: Rachita Kothiyal <rachita@in.ibm.com> Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] kdump: dynamic per cpu allocation of memory for saving cpu registersVivek Goyal2006-01-10
| | | | | | | | | | | | | | | | | | | | | - In case of system crash, current state of cpu registers is saved in memory in elf note format. So far memory for storing elf notes was being allocated statically for NR_CPUS. - This patch introduces dynamic allocation of memory for storing elf notes. It uses alloc_percpu() interface. This should lead to better memory usage. - Introduced based on Andi Kleen's and Eric W. Biederman's suggestions. - This patch also moves memory allocation for elf notes from architecture dependent portion to architecture independent portion. Now crash_notes is architecture independent. The whole idea is that size of memory to be allocated per cpu (MAX_NOTE_BYTES) can be architecture dependent and allocation of this memory can be architecture independent. Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] kexec code cleanupManeesh Soni2005-06-25
| | | | | | | | | | | | | | | | | o Following patch provides purely cosmetic changes and corrects CodingStyle guide lines related certain issues like below in kexec related files o braces for one line "if" statements, "for" loops, o more than 80 column wide lines, o No space after "while", "for" and "switch" key words o Changes: o take-2: Removed the extra tab before "case" key words. o take-3: Put operator at the end of line and space before "*/" Signed-off-by: Maneesh Soni <maneesh@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] kdump: Use real pt_regs from exceptionAlexander Nyberg2005-06-25
| | | | | | | | | | | | | | | | | | | | | Makes kexec_crashdump() take a pt_regs * as an argument. This allows to get exact register state at the point of the crash. If we come from direct panic assertion NULL will be passed and the current registers saved before crashdump. This hooks into two places: die(): check the conditions under which we will panic when calling do_exit and go there directly with the pt_regs that caused the fatal fault. die_nmi(): If we receive an NMI lockup while in the kernel use the pt_regs and go directly to crash_kexec(). We're probably nested up badly at this point so this might be the only chance to escape with proper information. Signed-off-by: Alexander Nyberg <alexn@telia.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] kexec: s390 supportHeiko Carstens2005-06-25
| | | | | | | | | | | | | | | | Add kexec support for s390 architecture. From: Milton Miller <miltonm@bga.com> - Fix passing of first argument to relocate_kernel assembly. - Fix Kconfig description. - Remove wrong comment and comments that describe obvious things. - Allow only KEXEC_TYPE_DEFAULT as image type -> dump not supported. Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] kexec: add kexec syscallsEric W. Biederman2005-06-25
This patch introduces the architecture independent implementation the sys_kexec_load, the compat_sys_kexec_load system calls. Kexec on panic support has been integrated into the core patch and is relatively clean. In addition the hopefully architecture independent option crashkernel=size@location has been docuemented. It's purpose is to reserve space for the panic kernel to live, and where no DMA transfer will ever be setup to access. Signed-off-by: Eric Biederman <ebiederm@xmission.com> Signed-off-by: Alexander Nyberg <alexn@telia.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>