aboutsummaryrefslogtreecommitdiff
path: root/arch/s390/kernel/head64.S
AgeCommit message (Collapse)Author
2014-02-05s390: fix kernel crash due to linkage stack instructionsMartin Schwidefsky
The kernel currently crashes with a low-address-protection exception if a user space process executes an instruction that tries to use the linkage stack. Set the base-ASTE origin and the subspace-ASTE origin of the dispatchable-unit-control-table to point to a dummy ASTE. Set up control register 15 to point to an empty linkage stack with no room left. A user space process with a linkage stack instruction will still crash but with a different exception which is correctly translated to a segmentation fault instead of a kernel oops. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-10-09s390/mm: let kernel text section always begin at 1MBHeiko Carstens
Let the kernel text section always begin at 1MB. This allows to always have a large frame in the identity mapping of the kernel image for beginning of the text section, if the machine has EDAT1 support. Moving the beginning from 64K to 1MB doesn't cost any memory, since we make the memory between 64K and 1MB available for the page allocator. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-07-20s390/comments: unify copyright messages and remove file namesHeiko Carstens
Remove the file name from the comment at top of many files. In most cases the file name was wrong anyway, so it's rather pointless. Also unify the IBM copyright statement. We did have a lot of sightly different statements and wanted to change them one after another whenever a file gets touched. However that never happened. Instead people start to take the old/"wrong" statements to use as a template for new files. So unify all of them in one go. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2011-10-30[S390] smp: external call vs. emergency signalMartin Schwidefsky
Use a sigp sense running to decide which signal processor order to use for an ipi. If the target cpu is running use external call, if the target cpu is not running use emergency signal. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-07-24[S390] initial cr0 bitsMartin Schwidefsky
Remove outdated bits from the initial cr0 register. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-07-24[S390] iucv cr0 enablement bitMartin Schwidefsky
Do not set the cr0 enablement bit for iucv by default in head[31|64].S, move the enablement to iucv_init in the iucv base layer. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-07-24[S390] fix s390 assembler code alignmentsJan Glauber
The alignment is missing for various global symbols in s390 assembly code. With a recent gcc and an instruction like stgrl this can lead to a specification exception if the instruction uses such a mis-aligned address. Specify the alignment explicitely and while add it define __ALIGN for s390 and use the ENTRY define to save some lines of code. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-05-12[S390] correct address of _stext with CONFIG_SHARED_KERNEL=yMartin Schwidefsky
As of git commit 1844c9bc0b2fed3023551c1affe033ab38e90b9a head64.S/head31.S are not included in head.S anymore but build as an extra object. This breaks shared kernel support because the .org statement in head64.S/head31.S for CONFIG_SHARED_KERNEL=y will have a different effect. The end address of the head.text section in head.o will be added to the .org value, to compensate for this subtract 0x11000 to get the required value of 0x100000 again. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-03-24[S390] fix boot failures with compressed kernelsMartin Schwidefsky
Fix two bugs with the kernel image compression: 1) reset the bss section of the compressed vmlinux 2) clear the high half of the registers for 64 bit early enough for the decompression step Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26[S390] add support for compressed kernelsMartin Schwidefsky
Add the "bzImage" compile target and the necessary code to generate compressed kernel images. The old style uncompressed "image" target is preserved, a simple make will build them both. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26[S390] zfcpdump: remove cross arch dump supportHeiko Carstens
Remove support to be able to dump 31 bit systems with a 64 bit dumper. This is mostly useless since no distro ships 31 bit kernels together with a 64 bit dumper. We also get rid of a bit of hacky code. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-12-07[S390] s390: clear high-order bits of registers after sam64Hendrik Brueckner
When the kernel is IPLed without the CLEAR option and switches to 64-bit, the high-order half of the registers might contain random values. This can cause addressing exceptions and the kernel enters an interrupt loop. Initialize the high-order half of the general purpose registers with zeros after switching to 64-bit mode. Cc: <stable@kernel.org> Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-11[S390] Limit cpu detection to 256 physical cpus.Heiko Carstens
Saves us more than 65k pointless IPIs. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-11[S390] Initialize __LC_THREAD_INFO early.Heiko Carstens
"lockdep: Fix backtraces" reveales a bug in early setup code: when lockdep tries to save a stack backtrace before setup_arch has been called the lowcore pointer for the current thread info pointer isn't initialized yet. However our save stack backtrace code relies on it. If the pointer isn't initialized the saved backtrace will have zero entries. lockdep however relies (correctly) on the fact that that cannot happen. A write access to some random memory region is the result. Fix this by initializing the thread info pointer early. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] eliminate ipl_device from lowcoreMartin Schwidefsky
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-31[PATCH] fast vdso implementation for CLOCK_THREAD_CPUTIME_IDMartin Schwidefsky
The extract cpu time instruction (ectg) instruction allows the user process to get the current thread cputime without calling into the kernel. The code that uses the instruction needs to switch to the access registers mode to get access to the per-cpu info page that contains the two base values that are needed to calculate the current cputime from the CPU timer with the ectg instruction. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25[S390] Remove initial kernel stack backchain initialization.Heiko Carstens
Early init code clears the backchain of the initial kernel stack frame. This is not necessary since it is pre initialized with zeros. Plus it was broken on 64 bit since it cleared only four of eight bytes. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25[S390] Add processor type march=z10 and a processor type safety check.Martin Schwidefsky
This patch adds the code generation option for IBM System z10 and adds a check in head[31,64].S to prevents the execution of a kernel compiled for a new processor type on an old machine. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-04-30[S390] System z large page support.Gerald Schaefer
This adds hugetlbfs support on System z, using both hardware large page support if available and software large page emulation on older hardware. Shared (large) page tables are implemented in software emulation mode, by using page->index of the first tail page from a compound large page to store page table information. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-04-30[S390] Convert machine feature detection code to C.Heiko Carstens
From: Heiko Carstens <heiko.carstens@de.ibm.com> From: Carsten Otte <cotte@de.ibm.com> This lets us use defines for the magic bits in machine flags instead of using plain numbers all over the place. In addition on newer machines features/facilities are indicated by the result of the stfl instruction. So we use these bits instead of trying to execute new instructions and check wether we get an exception or not. Also the mvpg instruction is always available when in zArch mode, whereas the idte instruction is only available in zArch mode. This results in some minor optimizations. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26[S390] Fix tlb flushing with idte.Martin Schwidefsky
The clear-by-asce operation of the idte instruction gets an asce (address-space-control-element) as argument to specify which TLBs need to get flushed. The current code passes a plain pointer to the start of the pgd without the additional bits which would make the pointer an asce. The current machines don't mind the difference but a future model might want to use the designation type control bits in the asce as a filter for the TLBs to flush. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-04-27[S390] zfcpdump support.Michael Holzheu
s390 machines provide hardware support for creating Linux dumps on SCSI disks. For creating a dump a special purpose dump Linux is used. The first 32 MB of memory are saved by the hardware before the dump Linux is booted. Via an SCLP interface, the saved memory can be accessed from Linux. This patch exports memory and registers of the crashed Linux to userspace via a debugfs file. For more information refer to Documentation/s390/zfcpdump.txt, which is included in this patch. Signed-off-by: Michael Holzheu <holzheu@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
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>
2007-02-21[S390] nss: Free unused memory in kernel image.Heiko Carstens
With CONFIG_SHARED_KERNEL the kernel text segment that might be in a read only memory sections starts at 1MB. Memory between 0x12000 and 0x100000 is unused then. Free this, so we have appr. an extra MB of memory available. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05[S390] Convert memory detection into C code.Heiko Carstens
Hopefully this will make it more maintainable and less error prone. Code makes use of search_exception_tables(). Since it calls this function before the kernel exeception table is sorted, there is an early call to sort_main_extable(). This way it's easy to use the already present infrastructure of fixup sections. Also this would allows to easily convert the rest of head[31|64].S into C code. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05[S390] boot from NSS supportHongjie Yang
Add support to boot from a named saved segment (NSS). Signed-off-by: Hongjie Yang <hongjie@us.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05[S390] Fix FCP dump feature detection.Heiko Carstens
FCP dump feature detection works only if the sclp command in head.S was succesful. Since the sclp command is skipped if diag260 works, we don't have any dump feature detection anymore. Bug was introduced with d57de5a36791cb1b7285649c62f183b0d3505f7d. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-01-09[S390] memory detection misses 128k.Hongjie Yang
Fix a memory leak problem in the memory detection routines. A memory leak of 128k occurs when we have a contiguous memory with mixed access-mode (read or write) ranges. Signed-off-by: Hongjie Yang <hongjie@us.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-12-04[S390] Memory detection fixes.Heiko Carstens
VMALLOC_END on 31bit should be 0x8000000UL instead of 0x7fffffffL. The page mask which is used to make sure memory_end is on 4MB/2MB boundary is wrong and not needed. Therefore remove it. Make sure a vmalloc area does also exist and work on (future) machines with 4TB and more memory. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-12-04[S390] Use diag260 for memory size detection.Heiko Carstens
Avoid the tprot loop if diag260 works and reports that there are no holes in memory. The tprot instruction can lead to a significant delay in the ipl process if the virtual guest has a lot of memory and the host is under memory pressure. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-10-04[S390] Remove crept in whitespace from head*.S again.Heiko Carstens
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2006-10-01[PATCH] Directed yield: direct yield of spinlocks for s390.Martin Schwidefsky
Use the new diagnose 0x9c in the spinlock implementation for s390. It yields the remaining timeslice of the virtual cpu that tries to acquire a lock to the virtual cpu that is the current holder of the lock. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-28[S390] Whitespace cleanup.Heiko Carstens
Huge s390 assembly files whitespace cleanup. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-20[S390] Use alternative user-copy operations for new hardware.Gerald Schaefer
This introduces new user-copy operations which are optimized for copying more than 256 Bytes on new hardware. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> 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>
2006-09-20[S390] initrd vs. bootmem bitmap.Heiko Carstens
Move initrd if the bitmap of the bootmem allocator would overwrite it. In addition this patch sets the default size and address of the initrd to 0. Therefore all boot loaders must set the initrd size and address correctly. This is especially relevant for ftp boot via HMC/SE, where this change requires a special patch file entry in the .ins file which sets these two values contained at address 0x10408 and 0x10410. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-07-18[S390] .align 4096 statements in head.SHeiko Carstens
SLES9 binutils don't like .align 4096 statements in head.S. Work around this by using .org statements. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-06-29[S390] head.S code moving.Heiko Carstens
There is almost no room left for any new code between 0x10000 and 0x10480. Move the code from 0x10000 to 0x11000. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-06-29[S390] memory detection.Heiko Carstens
The wrong base register is used to read a value from the sclp data structure. The value is used to calculate the memory size. Use correct register %r4. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2005-11-07[PATCH] s390: merge common parts of head.S and head64.SHeiko Carstens
Merge common parts of head.S and head64.S into head.S and move architecture specific parts to head31.S and head64.S respectively. Saves us ~500 lines of duplicated assembly code. 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>
2005-11-07[PATCH] s390: memory query wait pswHeiko Carstens
Don't switch back to 24 bit addressing mode when waiting for an external interrupt and set the correct bit in wait PSW (external mask instead of I/O mask). Signed-off-by: Heiko Carstens <heiko.carstens@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>
2005-10-30[PATCH] s390: export ipl device parametersHeiko Carstens
Sysfs interface to export ipl device parameters. Dependent on the ipl type the interface will look like this: - ccw ipl: /sys/firmware/ipl/device /ipl_type - fcp ipl: /sys/firmware/ipl/binary_parameter /bootprog /br_lba /device /ipl_type /lun /scp_data /wwpn - otherwise (unknown that is): /sys/firmware/ipl/ipl_type Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Greg KH <greg@kroah.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>
2005-09-09kbuild: m68k,parisc,ppc,ppc64,s390,xtensa use generic asm-offsets.h supportSam Ravnborg
Delete obsoleted parts form arch makefiles and rename to asm-offsets.h Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2005-07-29[PATCH] s390: check for interrupt before waitingHeiko Carstens
The patch that introduced waiting for interrupts after resetting the reader can cause the boot to fail because the system is waiting for an interrupt that will never arrive. Add code to check if an interrupt is supposed to arrive before waiting endlessly. Signed-off-by: Heiko Carstens <heiko.carstens@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>
2005-07-27[PATCH] s390: external call performanceHeiko Carstens
The kernel uses the SIGP external call order code to signal other CPUs. When running with dedicated CPUs external calls don't get delivered immediately but within a fixed polling invervall. This can lead to delays where the system appears to do nothing. Replace the SIGP external call order with the SIGP emergency call order since this one gets delivered immediately. 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>
2005-06-21[PATCH] s390: pending interrupt after ipl from readerHeiko Carstens
Wait for interrupt and clear status pending after resetting the reader. 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>
2005-06-21[PATCH] s390: memory detection > 32GBHeiko Carstens
The kernel takes a very long time to boot if the memory size is bigger then 32767 MB. The memory size is contained in a structure created by an sclp call. The kernel accesses the field with a LH instrution which performs a sign extension of a 16 bit word. In the case of a memory size with bit 2^15 set this results in a very large value and the memory detection just loops for a long time. In addition if more then 64 GB are used on a 64 bit system the memory size is read from an incorrect storage location. Use zero-extention to read the 16 bit memory size and the correct offset to read the 4 byte memory size on 64 bit. 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-rc2v2.6.12-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!