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* s390: correct _stext offsetVasily Gorbik2018-07-021-25/+15
| | | | | | | | | | | | | | | | | Avoid unnecessary rewrite of psw and merge _stext into startup_continue. This allows to move _stext definition to vmlinux.lds.S, where _etext is also defined and set _stext to the actual beginning of .text at 0x100000. This fixes the problem with setting the last .text page as not-executable due to vmem_map_init relying on page alinged _stext and _etext. Fixes: bd79d6632958 ("s390/decompressor: trim the kernel image up to 1M") Reported-by: Nils Hoppmann <niho@de.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: get rid of the first mb of uncompressed imageVasily Gorbik2018-07-021-1/+0
| | | | | | | | | | | Instead of generating uncompressed kernel image starting at 0, filling first mb with zeros (with ".org 0x100000") and then trimming it off from vmlinux.bin before compression, simply generate a kernel image starting from 0x100000. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: remove unused _ehead symbolVasily Gorbik2018-07-021-2/+0
| | | | | | | | | | Since startup code now reserves memory ranges [0, PARMAREA_END] and [_stext, <end of kernel>] _ehead symbol is not used and could be cleaned up. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/boot: make head.S and als.c be part of the decompressor onlyVasily Gorbik2018-06-251-1/+1
| | | | | | | | | | Since uncompressed kernel image does not have to be bootable anymore, move head.S, head_kdump.S and als.c to boot/ folder and compile them in just in the decompressor. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/decompressor: trim the kernel image up to 1MVasily Gorbik2018-06-251-1/+1
| | | | | | | | | | | Move head64.S main kernel entry point "startup_continue" to 0x100000 and trim everything which is below 1M during build. So, that the decompressor would unpack the main kernel image, move it to 0x100000 and jump to startup_continue. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/early: move functions which may not access bss section to extra fileHeiko Carstens2018-05-091-2/+6
| | | | | | | | | | Move functions which may not access bss section to extra file. This makes it easier to verify that all early functions which may not rely on an initialized bss section are not accessing it. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: remove all code using the access register modeMartin Schwidefsky2017-11-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The vdso code for the getcpu() and the clock_gettime() call use the access register mode to access the per-CPU vdso data page with the current code. An alternative to the complicated AR mode is to use the secondary space mode. This makes the vdso faster and quite a bit simpler. The downside is that the uaccess code has to be changed quite a bit. Which instructions are used depends on the machine and what kind of uaccess operation is requested. The instruction dictates which ASCE value needs to be loaded into %cr1 and %cr7. The different cases: * User copy with MVCOS for z10 and newer machines The MVCOS instruction can copy between the primary space (aka user) and the home space (aka kernel) directly. For set_fs(KERNEL_DS) the kernel ASCE is loaded into %cr1. For set_fs(USER_DS) the user space is already loaded in %cr1. * User copy with MVCP/MVCS for older machines To be able to execute the MVCP/MVCS instructions the kernel needs to switch to primary mode. The control register %cr1 has to be set to the kernel ASCE and %cr7 to either the kernel ASCE or the user ASCE dependent on set_fs(KERNEL_DS) vs set_fs(USER_DS). * Data access in the user address space for strnlen / futex To use "normal" instruction with data from the user address space the secondary space mode is used. The kernel needs to switch to primary mode, %cr1 has to contain the kernel ASCE and %cr7 either the user ASCE or the kernel ASCE, dependent on set_fs. To load a new value into %cr1 or %cr7 is an expensive operation, the kernel tries to be lazy about it. E.g. for multiple user copies in a row with MVCP/MVCS the replacement of the vdso ASCE in %cr7 with the user ASCE is done only once. On return to user space a CPU bit is checked that loads the vdso ASCE again. To enable and disable the data access via the secondary space two new functions are added, enable_sacf_uaccess and disable_sacf_uaccess. The fact that a context is in secondary space uaccess mode is stored in the mm_segment_t value for the task. The code of an interrupt may use set_fs as long as it returns to the previous state it got with get_fs with another call to set_fs. The code in finish_arch_post_lock_switch simply has to do a set_fs with the current mm_segment_t value for the task. For CPUs with MVCOS: CPU running in | %cr1 ASCE | %cr7 ASCE | --------------------------------------|-----------|-----------| user space | user | vdso | kernel, USER_DS, normal-mode | user | vdso | kernel, USER_DS, normal-mode, lazy | user | user | kernel, USER_DS, sacf-mode | kernel | user | kernel, KERNEL_DS, normal-mode | kernel | vdso | kernel, KERNEL_DS, normal-mode, lazy | kernel | kernel | kernel, KERNEL_DS, sacf-mode | kernel | kernel | For CPUs without MVCOS: CPU running in | %cr1 ASCE | %cr7 ASCE | --------------------------------------|-----------|-----------| user space | user | vdso | kernel, USER_DS, normal-mode | user | vdso | kernel, USER_DS, normal-mode lazy | kernel | user | kernel, USER_DS, sacf-mode | kernel | user | kernel, KERNEL_DS, normal-mode | kernel | vdso | kernel, KERNEL_DS, normal-mode, lazy | kernel | kernel | kernel, KERNEL_DS, sacf-mode | kernel | kernel | The lines with "lazy" refer to the state after a copy via the secondary space with a delayed reload of %cr1 and %cr7. There are three hardware address spaces that can cause a DAT exception, primary, secondary and home space. The exception can be related to four different fault types: user space fault, vdso fault, kernel fault, and the gmap faults. Dependent on the set_fs state and normal vs. sacf mode there are a number of fault combinations: 1) user address space fault via the primary ASCE 2) gmap address space fault via the primary ASCE 3) kernel address space fault via the primary ASCE for machines with MVCOS and set_fs(KERNEL_DS) 4) vdso address space faults via the secondary ASCE with an invalid address while running in secondary space in problem state 5) user address space fault via the secondary ASCE for user-copy based on the secondary space mode, e.g. futex_ops or strnlen_user 6) kernel address space fault via the secondary ASCE for user-copy with secondary space mode with set_fs(KERNEL_DS) 7) kernel address space fault via the primary ASCE for user-copy with secondary space mode with set_fs(USER_DS) on machines without MVCOS. 8) kernel address space fault via the home space ASCE Replace user_space_fault() with a new function get_fault_type() that can distinguish all four different fault types. With these changes the futex atomic ops from the kernel and the strnlen_user will get a little bit slower, as well as the old style uaccess with MVCP/MVCS. All user accesses based on MVCOS will be as fast as before. On the positive side, the user space vdso code is a lot faster and Linux ceases to use the complicated AR mode. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
* License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman2017-11-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* s390/time: add support for the TOD clock epoch extensionMartin Schwidefsky2017-07-261-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | The TOD epoch extension adds 8 epoch bits to the TOD clock to provide a continuous clock after 2042/09/17. The store-clock-extended (STCKE) instruction will store the epoch index in the first byte of the 16 bytes stored by the instruction. The read_boot_clock64 and the read_presistent_clock64 functions need to take the additional bits into account to give the correct result after 2042/09/17. The clock-comparator register will stay 64 bit wide. The comparison of the clock-comparator with the TOD clock is limited to bytes 1 to 8 of the extended TOD format. To deal with the overflow problem due to an epoch change the clock-comparator sign control in CR0 can be used to switch the comparison of the 64-bit TOD clock with the clock-comparator to a signed comparison. The decision between the signed vs. unsigned clock-comparator comparisons is done at boot time. Only if the TOD clock is in the second half of a 142 year epoch the signed comparison is used. This solves the epoch overflow issue as long as the machine is booted at least once in an epoch. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/cpumf: simplify detection of guest samplesMartin Schwidefsky2017-04-051-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are three different code levels in regard to the identification of guest samples. They differ in the way the LPP instruction is used. 1) Old kernels without the LPP instruction. The guest program parameter is always zero. 2) Newer kernels load the process pid into the program parameter with LPP. The guest program parameter is non-zero if the guest executes in a process != idle. 3) The latest kernels load ((1UL << 31) | pid) with LPP to make the value non-zero even for the idle task. The guest program parameter is non-zero if the guest is running. All kernels load the process pid to CR4 on context switch. The CPU sampling code uses the value in CR4 to decide between guest and host samples in case the guest program parameter is zero. The three cases: 1) CR4==pid, gpp==0 2) CR4==pid, gpp==pid 3) CR4==pid, gpp==((1UL << 31) | pid) The load-control instruction to load the pid into CR4 is expensive and the goal is to remove it. To distinguish the host CR4 from the guest pid for the idle process the maximum value 0xffff for the PASN is used. This adds a fourth case for a guest OS with an updated kernel: 4) CR4==0xffff, gpp=((1UL << 31) | pid) The host kernel will have CR4==0xffff and will use (gpp!=0 || CR4!==0xffff) to identify guest samples. This works nicely with all 4 cases, the only possible issue would be a guest with an old kernel (gpp==0) and a process pid of 0xffff. Well, don't do that.. Suggested-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/thread_info: get rid of THREAD_ORDER defineHeiko Carstens2016-11-231-1/+1
| | | | | | | | | | We have the s390 specific THREAD_ORDER define and the THREAD_SIZE_ORDER define which is also used in common code. Both have exactly the same semantics. Therefore get rid of THREAD_ORDER and always use THREAD_SIZE_ORDER instead. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: move thread_info into task_structHeiko Carstens2016-11-111-3/+2
| | | | | | | | This is the s390 variant of commit 15f4eae70d36 ("x86: Move thread_info into task_struct"). Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/cpumf: Fix lpp detectionChristian Borntraeger2016-03-081-1/+1
| | | | | | | | | | | | | we have to check bit 40 of the facility list before issuing LPP and not bit 48. Otherwise a guest running on a system with "The decimal-floating-point zoned-conversion facility" and without the "The set-program-parameters facility" might crash on an lpp instruction. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Cc: stable@vger.kernel.org # v4.4+ Fixes: e22cf8ca6f75 ("s390/cpumf: rework program parameter setting to detect guest samples") Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/facilities: always use lowcore's stfle field for storing facility bitsHeiko Carstens2015-12-181-1/+1
| | | | | | | | | | | | | | | | | | | head.s contains an stfle instruction which stores it result at the storage location that is assigned to the stfl instruction. This is currently no problem, since we only care about one double word. However if the number of double words in the ALS bitfield grows the current code is not very stable. E.g. before issuing the stfle command the memory to which it stores must be cleared, since the instruction may or may not clear memory contents where no bits are set. In order to simplify the code a bit always use the storage location that we reserved for the stfle result. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/cpumf: rework program parameter setting to detect guest samplesChristian Borntraeger2015-10-141-1/+6
| | | | | | | | | | | | | | | | | | | | | | The program parameter can be used to mark hardware samples with some token. Previously, it was used to mark guest samples only. Improve the program parameter doubleword by combining two parts, the leftmost LPP part and the rightmost PID part. Set the PID part for processes by using the task PID. To distinguish host and guest samples for the kernel (PID part is zero), the guest must always set the program paramater to a non-zero value. Use the leftmost bit in the LPP part of the program parameter to be able to detect guest kernel samples. [brueckner@linux.vnet.ibm.com]: Split __LC_CURRENT and introduced __LC_LPP. Corrected __LC_CURRENT users and adjusted assembler parts. And updated the commit message accordingly. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: fix kernel crash due to linkage stack instructionsMartin Schwidefsky2014-02-051-2/+5
| | | | | | | | | | | | | | | 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>
* s390/mm: let kernel text section always begin at 1MBHeiko Carstens2012-10-091-3/+0
| | | | | | | | | | | 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>
* s390/comments: unify copyright messages and remove file namesHeiko Carstens2012-07-201-3/+1
| | | | | | | | | | | | | | 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>
* [S390] smp: external call vs. emergency signalMartin Schwidefsky2011-10-301-1/+1
| | | | | | | | 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>
* [S390] initial cr0 bitsMartin Schwidefsky2011-07-241-1/+1
| | | | | | Remove outdated bits from the initial cr0 register. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] iucv cr0 enablement bitMartin Schwidefsky2011-07-241-1/+1
| | | | | | | 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>
* [S390] fix s390 assembler code alignmentsJan Glauber2011-07-241-6/+5
| | | | | | | | | | | | 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>
* [S390] correct address of _stext with CONFIG_SHARED_KERNEL=yMartin Schwidefsky2010-05-121-1/+1
| | | | | | | | | | | 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>
* [S390] fix boot failures with compressed kernelsMartin Schwidefsky2010-03-241-2/+0
| | | | | | | | | 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>
* [S390] add support for compressed kernelsMartin Schwidefsky2010-02-261-12/+12
| | | | | | | | 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>
* [S390] zfcpdump: remove cross arch dump supportHeiko Carstens2010-02-261-69/+1
| | | | | | | | | | 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>
* [S390] s390: clear high-order bits of registers after sam64Hendrik Brueckner2009-12-071-0/+3
| | | | | | | | | | | | | | 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>
* [S390] Limit cpu detection to 256 physical cpus.Heiko Carstens2009-09-111-5/+3
| | | | | | | 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>
* [S390] Initialize __LC_THREAD_INFO early.Heiko Carstens2009-09-111-0/+1
| | | | | | | | | | | | | | | | | "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>
* [S390] eliminate ipl_device from lowcoreMartin Schwidefsky2009-03-261-1/+0
| | | | Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [PATCH] fast vdso implementation for CLOCK_THREAD_CPUTIME_IDMartin Schwidefsky2008-12-311-0/+2
| | | | | | | | | | | 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>
* [S390] Remove initial kernel stack backchain initialization.Heiko Carstens2008-12-251-1/+0
| | | | | | | | | 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>
* [S390] Add processor type march=z10 and a processor type safety check.Martin Schwidefsky2008-12-251-23/+0
| | | | | | | | 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>
* [S390] System z large page support.Gerald Schaefer2008-04-301-1/+1
| | | | | | | | | | | 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>
* [S390] Convert machine feature detection code to C.Heiko Carstens2008-04-301-62/+0
| | | | | | | | | | | | | | | | | | | 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>
* [S390] Fix tlb flushing with idte.Martin Schwidefsky2008-01-261-1/+1
| | | | | | | | | | | | 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>
* [S390] zfcpdump support.Michael Holzheu2007-04-271-1/+71
| | | | | | | | | | | | | | 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>
* [S390] Fixed handling of access register mode faults.Gerald Schaefer2007-03-051-3/+8
| | | | | | | | | | | | | | | | | | | 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>
* [S390] nss: Free unused memory in kernel image.Heiko Carstens2007-02-211-14/+2
| | | | | | | | | | 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>
* [S390] Convert memory detection into C code.Heiko Carstens2007-02-051-175/+0
| | | | | | | | | | | | | | 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>
* [S390] boot from NSS supportHongjie Yang2007-02-051-23/+7
| | | | | | | 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>
* [S390] Fix FCP dump feature detection.Heiko Carstens2007-02-051-1/+5
| | | | | | | | | | 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>
* [S390] memory detection misses 128k.Hongjie Yang2007-01-091-1/+11
| | | | | | | | | 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>
* [S390] Memory detection fixes.Heiko Carstens2006-12-041-4/+0
| | | | | | | | | | | 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>
* [S390] Use diag260 for memory size detection.Heiko Carstens2006-12-041-2/+15
| | | | | | | | | | 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>
* [S390] Remove crept in whitespace from head*.S again.Heiko Carstens2006-10-041-6/+6
| | | | Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
* [PATCH] Directed yield: direct yield of spinlocks for s390.Martin Schwidefsky2006-10-011-0/+11
| | | | | | | | | | | 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>
* [S390] Whitespace cleanup.Heiko Carstens2006-09-281-216/+216
| | | | | | | 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>
* [S390] Use alternative user-copy operations for new hardware.Gerald Schaefer2006-09-201-0/+13
| | | | | | | | 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>
* [S390] convert some assembler to C.Heiko Carstens2006-09-201-14/+25
| | | | | | | 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>
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