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2007-03-05[S390] Fixed handling of access register mode faults.Gerald Schaefer
Replaced check_user_space() + __check_access_register with the new check_space(). The old functions made wrong assumptions about kernel and user space when the kernel and user address spaces are switched (kernel in home space, user in primary/secondary space). Secondly the user process can switch to the accress register mode if it is running in primary or secondary mode. In addition it can load an arbitrary value to the access registers. If any other value than 0 for primary space or 1 for secondary space is loaded and memory is accessed using the base register related to the access register, the program should be terminated with a SIGSEGV. To achieve that the DUALD pointer in the DUCT and the PSALD pointer in the PASTE need to point to an array of 8 invalid access-list entries to get a ALEN-translation exception if an invalid alet is used. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-11[PATCH] Consolidate bust_spinlocks()Kirill Korotaev
Part of long forgotten patch http://groups.google.com/group/fa.linux.kernel/msg/e98e941ce1cf29f6?dmode=source Since then, m32r grabbed two copies. Leave s390 copy because of important absence of CONFIG_VT, but remove references to non-existent timerlist_lock. ia64 also loses timerlist_lock. Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Andi Kleen <ak@muc.de> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Hirokazu Takata <takata@linux-m32r.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
2007-02-05[S390] Get rid of a lot of sparse warnings.Heiko Carstens
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-12-04[S390] pfault code cleanup.Heiko Carstens
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-10-06[S390] irq change build fixes.Heiko Carstens
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-29[PATCH] pidspace: is_init()Sukadev Bhattiprolu
This is an updated version of Eric Biederman's is_init() patch. (http://lkml.org/lkml/2006/2/6/280). It applies cleanly to 2.6.18-rc3 and replaces a few more instances of ->pid == 1 with is_init(). Further, is_init() checks pid and thus removes dependency on Eric's other patches for now. Eric's original description: There are a lot of places in the kernel where we test for init because we give it special properties. Most significantly init must not die. This results in code all over the kernel test ->pid == 1. Introduce is_init to capture this case. With multiple pid spaces for all of the cases affected we are looking for only the first process on the system, not some other process that has pid == 1. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Serge Hallyn <serue@us.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: <lxc-devel@lists.sourceforge.net> Acked-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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>
2006-09-28[S390] init task memory faults.Akinobu Mita
Lock for mmap_sem is missing on page fault retry for init task when it fails due to out of memory. Signed-off-by: Akinobu Mita <mita@miraclelinux.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-20[S390] add kprobes support.Michael Grundy
Signed-off-by: Michael Grundy <grundym@us.ibm.com> Signed-off-by: David Wilder <dwilder@us.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-07-12[S390] Fix sparse warnings.Heiko Carstens
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-06-30Remove obsolete #include <linux/config.h>Jörn Engel
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-01-06[PATCH] s390: cleanup KconfigMartin Schwidefsky
Sanitize some s390 Kconfig options. We have ARCH_S390, ARCH_S390X, ARCH_S390_31, 64BIT, S390_SUPPORT and COMPAT. Replace these 6 options by S390, 64BIT and COMPAT. 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>
2005-11-09[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>
2005-11-07[PATCH] s390: remove pagex supportMartin Schwidefsky
Remove pagex pseudo page fault code. It does not work together with the system call speedup that makes the complete system call path enabled for interrupts. To make pagex and the syscall speedup code work together we would have to add code to the program check handler to do a critical section cleanup like the asynchronous interrupt code. This would make program checks slower. Not what we want. Newer versions of z/VM have the improved pfault pseudo page fault interface. This replaces the old pagex interface and does not have the problem. So its better to just rip out the pagex code. 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>
2005-09-05[PATCH] s390: pfault interrupt raceMartin Schwidefsky
There is a race in pfault_interrupt. That function gets called two times for each pfault notification. Once with a subcode of 0 to indicate that a real page is not available and once with a subcode of 0x80 to indicate that the page is present again. Since the two external interrupts can be delivered on two different cpus the order in which the two calls are made is unpredictable. It is possible that the subcode 0x80 interrupt is completed before the subcode 0x00 interrupt has done the wake_up() call. To avoid calling wake_up() on an already removed task structure proper task structure reference counting is needed. Increase the reference counter in the subcode 0x00 interrupt before setting pfault_wait to zero and return the reference after the wake_up call. 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>
2005-06-04[PATCH] s390: in_interrupt vs. in_atomicMartin Schwidefsky
The condition for no context in do_exception checks for hard and soft interrupts by using in_interrupt() but not for preemption. This is bad for the users of __copy_from/to_user_inatomic because the fault handler might call schedule although the preemption count is != 0. Use in_atomic() instead in_interrupt(). 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!