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path: root/include/asm-s390/lowcore.h
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2007-02-05[S390] noexec protectionGerald Schaefer
This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-12-04[S390] Reset infrastructure for re-IPL.Heiko Carstens
In case of re-IPL and diag308 doesn't work we have to reset all devices manually and wait synchronously that each reset finished. This patch adds the necessary infrastucture and the first exploiter of it. Subsystems that need to add a function that needs to be called at re-IPL may register/unregister this function via struct reset_call { struct reset_call *next; void (*fn)(void); }; void register_reset_call(struct reset_call *reset); void unregister_reset_call(struct reset_call *reset); When the registered function get called the context is: - all cpus beside the current one are stopped - all machine checks and interrupts are disabled - prefixing is disabled - a default machine check handler is available for use The registered functions may not take any locks are sleep. For the common I/O layer part of this patch: Introduce a reset_call css_reset that does the following: - clear all subchannels - perform a rchp on all channel paths and wait for the resulting machine checks This replaces the calls to clear_all_subchannels() and cio_reset_channel_paths() for kexec and ccw reipl. reipl_ccw_dev() now uses reipl_find_schid() to determine the subchannel id for a given device id. Also remove cio_reset_channel_paths() and friends since they are not needed anymore. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-28[S390] Inline assembly cleanup.Martin Schwidefsky
Major cleanup of all s390 inline assemblies. They now have a common coding style. Quite a few have been shortened, mainly by using register asm variables. Use of the EX_TABLE macro helps as well. The atomic ops, bit ops and locking inlines new use the Q-constraint if a newer gcc is used. That results in slightly better code. Thanks to Christian Borntraeger for proof reading the changes. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-20[S390] convert some assembler to C.Heiko Carstens
Convert GET_IPL_DEVICE assembler macro to C function. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-20[S390] ipl/dump on panic.Michael Holzheu
It is now possible to specify a ccw/fcp dump device which is used to automatically create a system dump in case of a kernel panic. The dump device can be configured under /sys/firmware/dump. In addition it is now possible to specify a ccw/fcp device which is used for the next reboot of Linux. The reipl device can be configured under /sys/firmware/reipl. Signed-off-by: Michael Holzheu <holzheu@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-06-20Merge git://git.infradead.org/hdrcleanup-2.6Linus Torvalds
* git://git.infradead.org/hdrcleanup-2.6: (63 commits) [S390] __FD_foo definitions. Switch to __s32 types in joystick.h instead of C99 types for consistency. Add <sys/types.h> to headers included for userspace in <linux/input.h> Move inclusion of <linux/compat.h> out of user scope in asm-x86_64/mtrr.h Remove struct fddi_statistics from user view in <linux/if_fddi.h> Move user-visible parts of drivers/s390/crypto/z90crypt.h to include/asm-s390 Revert include/media changes: Mauro says those ioctls are only used in-kernel(!) Include <linux/types.h> and use __uXX types in <linux/cramfs_fs.h> Use __uXX types in <linux/i2o_dev.h>, include <linux/ioctl.h> too Remove private struct dx_hash_info from public view in <linux/ext3_fs.h> Include <linux/types.h> and use __uXX types in <linux/affs_hardblocks.h> Use __uXX types in <linux/divert.h> for struct divert_blk et al. Use __u32 for elf_addr_t in <asm-powerpc/elf.h>, not u32. It's user-visible. Remove PPP_FCS from user view in <linux/ppp_defs.h>, remove __P mess entirely Use __uXX types in user-visible structures in <linux/nbd.h> Don't use 'u32' in user-visible struct ip_conntrack_old_tuple. Use __uXX types for S390 DASD volume label definitions which are user-visible S390 BIODASDREADCMB ioctl should use __u64 not u64 type. Remove unneeded inclusion of <linux/time.h> from <linux/ufs_fs.h> Fix private integer types used in V4L2 ioctls. ... Manually resolve conflict in include/linux/mtd/physmap.h
2006-06-05[PATCH] s390: cio non-unique path group idsPeter Oberparleiter
From: Peter Oberparleiter <peter.oberparleiter@de.ibm.com> The path grouping can fail due to non-unique pathgroup-IDs. The source for the CPU-ID part of the ID was incorrectly specified on 64 bit systems. Additionally, the length of the ID was too large due to incorrect data packing declaration. Fix CPU-ID lowcore address and add missing packing declaration. Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-26Don't include linux/config.h from anywhere else in include/David Woodhouse
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-11-09[PATCH] s390: "extern inline" -> "static inline"Adrian Bunk
"extern inline" -> "static inline" Signed-off-by: Adrian Bunk <bunk@stusta.de> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05[PATCH] s390: machine check handler bugsMartin Schwidefsky
The new machine check handler still has a few bugs. 1) The system entry time has to be stored in the machine check handler, 2) the machine check return psw may not be stored at the usual place because it might overwrite the return psw of the interrupted context, 3) the return address for the call to s390_handle_mcck in the i/o interrupt handler is not correct, 4) the system call cleanup has to take the different save area of the machine check handler into account, 5) the machine check handler may not call UPDATE_VTIME before CREATE_STACK_FRAME, and 6) the io leave path needs a critical section cleanup to make sure that the TIF_MCCK_PENDING bit is really checked before switching back to user space. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27[PATCH] s390: spin lock retryMartin Schwidefsky
Split spin lock and r/w lock implementation into a single try which is done inline and an out of line function that repeatedly tries to get the lock before doing the cpu_relax(). Add a system control to set the number of retries before a cpu is yielded. The reason for the spin lock retry is that the diagnose 0x44 that is used to give up the virtual cpu is quite expensive. For spin locks that are held only for a short period of time the costs of the diagnoses outweights the savings for spin locks that are held for a longer timer. The default retry count is 1000. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25[PATCH] s390: improved machine check handlingHeiko Carstens
Improved machine check handling. Kernel is now able to receive machine checks while in kernel mode (system call, interrupt and program check handling). Also register validation is now performed. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!