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* 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>
* sparc64: Add 16GB hugepage supportNitin Gupta2017-08-151-1/+1
| | | | | | | | | | | | | | | | | | | | Adds support for 16GB hugepage size. To use this page size use kernel parameters as: default_hugepagesz=16G hugepagesz=16G hugepages=10 Testing: Tested with the stream benchmark which allocates 48G of arrays backed by 16G hugepages and does RW operation on them in parallel. Orabug: 25362942 Cc: Anthony Yznaga <anthony.yznaga@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: Nitin Gupta <nitin.m.gupta@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* sparc64: Prevent perf from running during super critical sectionsRob Gardner2017-07-181-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fixes another cause of random segfaults and bus errors that may occur while running perf with the callgraph option. Critical sections beginning with spin_lock_irqsave() raise the interrupt level to PIL_NORMAL_MAX (14) and intentionally do not block performance counter interrupts, which arrive at PIL_NMI (15). But some sections of code are "super critical" with respect to perf because the perf_callchain_user() path accesses user space and may cause TLB activity as well as faults as it unwinds the user stack. One particular critical section occurs in switch_mm: spin_lock_irqsave(&mm->context.lock, flags); ... load_secondary_context(mm); tsb_context_switch(mm); ... spin_unlock_irqrestore(&mm->context.lock, flags); If a perf interrupt arrives in between load_secondary_context() and tsb_context_switch(), then perf_callchain_user() could execute with the context ID of one process, but with an active TSB for a different process. When the user stack is accessed, it is very likely to incur a TLB miss, since the h/w context ID has been changed. The TLB will then be reloaded with a translation from the TSB for one process, but using a context ID for another process. This exposes memory from one process to another, and since it is a mapping for stack memory, this usually causes the new process to crash quickly. This super critical section needs more protection than is provided by spin_lock_irqsave() since perf interrupts must not be allowed in. Since __tsb_context_switch already goes through the trouble of disabling interrupts completely, we fix this by moving the secondary context load down into this better protected region. Orabug: 25577560 Signed-off-by: Dave Aldridge <david.j.aldridge@oracle.com> Signed-off-by: Rob Gardner <rob.gardner@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* sparc64: mm: fix copy_tsb to correctly copy huge page TSBsMike Kravetz2017-06-061-4/+7
| | | | | | | | | | | | | | | | | | | | | | When a TSB grows beyond its current capacity, a new TSB is allocated and copy_tsb is called to copy entries from the old TSB to the new. A hash shift based on page size is used to calculate the index of an entry in the TSB. copy_tsb has hard coded PAGE_SHIFT in these calculations. However, for huge page TSBs the value REAL_HPAGE_SHIFT should be used. As a result, when copy_tsb is called for a huge page TSB the entries are placed at the incorrect index in the newly allocated TSB. When doing hardware table walk, the MMU does not match these entries and we end up in the TSB miss handling code. This code will then create and write an entry to the correct index in the TSB. We take a performance hit for the table walk miss and recreation of these entries. Pass a new parameter to copy_tsb that is the page size shift to be used when copying the TSB. Suggested-by: Anthony Yznaga <anthony.yznaga@oracle.com> Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* sparc64: Multi-page size supportNitin Gupta2017-02-231-18/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | Add support for using multiple hugepage sizes simultaneously on mainline. Currently, support for 256M has been added which can be used along with 8M pages. Page tables are set like this (e.g. for 256M page): VA + (8M * x) -> PA + (8M * x) (sz bit = 256M) where x in [0, 31] and TSB is set similarly: VA + (4M * x) -> PA + (4M * x) (sz bit = 256M) where x in [0, 63] - Testing Tested on Sonoma (which supports 256M pages) by running stream benchmark instances in parallel: one instance uses 8M pages and another uses 256M pages, consuming 48G each. Boot params used: default_hugepagesz=256M hugepagesz=256M hugepages=300 hugepagesz=8M hugepages=10000 Signed-off-by: Nitin Gupta <nitin.m.gupta@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* sparc: Don't leak context bits into thread->fault_addressDavid S. Miller2016-07-271-2/+10
| | | | | | | | | | | | | | | | On pre-Niagara systems, we fetch the fault address on data TLB exceptions from the TLB_TAG_ACCESS register. But this register also contains the context ID assosciated with the fault in the low 13 bits of the register value. This propagates into current_thread_info()->fault_address and can cause trouble later on. So clear the low 13-bits out of the TLB_TAG_ACCESS value in the cases where it matters. Reported-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* sparc64: Fix corrupted thread fault code.David S. Miller2014-10-181-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Every path that ends up at do_sparc64_fault() must install a valid FAULT_CODE_* bitmask in the per-thread fault code byte. Two paths leading to the label winfix_trampoline (which expects the FAULT_CODE_* mask in register %g4) were not doing so: 1) For pre-hypervisor TLB protection violation traps, if we took the 'winfix_trampoline' path we wouldn't have %g4 initialized with the FAULT_CODE_* value yet. Resulting in using the TLB_TAG_ACCESS register address value instead. 2) In the TSB miss path, when we notice that we are going to use a hugepage mapping, but we haven't allocated the hugepage TSB yet, we still have to take the window fixup case into consideration and in that particular path we leave %g4 not setup properly. Errors on this sort were largely invisible previously, but after commit 4ccb9272892c33ef1c19a783cfa87103b30c2784 ("sparc64: sun4v TLB error power off events") we now have a fault_code mask bit (FAULT_CODE_BAD_RA) that triggers due to this bug. FAULT_CODE_BAD_RA triggers because this bit is set in TLB_TAG_ACCESS (see #1 above) and thus we get seemingly random bus errors triggered for user processes. Fixes: 4ccb9272892c ("sparc64: sun4v TLB error power off events") Reported-by: Meelis Roos <mroos@linux.ee> Signed-off-by: David S. Miller <davem@davemloft.net>
* sparc64: Move from 4MB to 8MB huge pages.David S. Miller2013-11-121-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The impetus for this is that we would like to move to 64-bit PMDs and PGDs, but that would result in only supporting a 42-bit address space with the current page table layout. It'd be nice to support at least 43-bits. The reason we'd end up with only 42-bits after making PMDs and PGDs 64-bit is that we only use half-page sized PTE tables in order to make PMDs line up to 4MB, the hardware huge page size we use. So what we do here is we make huge pages 8MB, and fabricate them using 4MB hw TLB entries. Facilitate this by providing a "REAL_HPAGE_SHIFT" which is used in places that really need to operate on hardware 4MB pages. Use full pages (512 entries) for PTE tables, and adjust PMD_SHIFT, PGD_SHIFT, and the build time CPP test as needed. Use a CPP test to make sure REAL_HPAGE_SHIFT and the _PAGE_SZHUGE_* we use match up. This makes the pgtable cache completely unused, so remove the code managing it and the state used in mm_context_t. Now we have less spinlocks taken in the page table allocation path. The technique we use to fabricate the 8MB pages is to transfer bit 22 from the missing virtual address into the PTEs physical address field. That takes care of the transparent huge pages case. For hugetlb, we fill things in at the PTE level and that code already puts the sub huge page physical bits into the PTEs, based upon the offset, so there is nothing special we need to do. It all just works out. So, a small amount of complexity in the THP case, but this code is about to get much simpler when we move the 64-bit PMDs as we can move away from the fancy 32-bit huge PMD encoding and just put a real PTE value in there. With bug fixes and help from Bob Picco. Signed-off-by: David S. Miller <davem@davemloft.net>
* sparc64: Fix tsb_grow() in atomic context.David S. Miller2013-02-201-4/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | If our first THP installation for an MM is via the set_pmd_at() done during khugepaged's collapsing we'll end up in tsb_grow() trying to do a GFP_KERNEL allocation with several locks held. Simply using GFP_ATOMIC in this situation is not the best option because we really can't have this fail, so we'd really like to keep this an order 0 GFP_KERNEL allocation if possible. Also, doing the TSB allocation from khugepaged is a really bad idea because we'll allocate it potentially from the wrong NUMA node in that context. So what we do is defer the hugepage TSB allocation until the first TLB miss we take on a hugepage. This is slightly tricky because we have to handle two unusual cases: 1) Taking the first hugepage TLB miss in the window trap handler. We'll call the winfix_trampoline when that is detected. 2) An initial TSB allocation via TLB miss races with a hugetlb fault on another cpu running the same MM. We handle this by unconditionally loading the TSB we see into the current cpu even if it's non-NULL at hugetlb_setup time. Reported-by: Meelis Roos <mroos@ut.ee> Signed-off-by: David S. Miller <davem@davemloft.net>
* sparc64: Support transparent huge pages.David Miller2012-10-091-6/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is relatively easy since PMD's now cover exactly 4MB of memory. Our PMD entries are 32-bits each, so we use a special encoding. The lowest bit, PMD_ISHUGE, determines the interpretation. This is possible because sparc64's page tables are purely software entities so we can use whatever encoding scheme we want. We just have to make the TLB miss assembler page table walkers aware of the layout. set_pmd_at() works much like set_pte_at() but it has to operate in two page from a table of non-huge PTEs, so we have to queue up TLB flushes based upon what mappings are valid in the PTE table. In the second regime we are going from huge-page to non-huge-page, and in that case we need only queue up a single TLB flush to push out the huge page mapping. We still have 5 bits remaining in the huge PMD encoding so we can very likely support any new pieces of THP state tracking that might get added in the future. With lots of help from Johannes Weiner. Signed-off-by: David S. Miller <davem@davemloft.net> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* sparc64: Fix sun4u execute bit check in TSB I-TLB load.David S. Miller2010-02-191-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Thanks to testcase and report from Brad Spengler: -------------------- #include <stdio.h> typedef int (* _wee)(void); int main(void) { char buf[8] = { '\x81', '\xc7', '\xe0', '\x08', '\x81', '\xe8', '\x00', '\x00' }; _wee wee; printf("%p\n", &buf); wee = (_wee)&buf; wee(); return 0; } -------------------- TSB I-tlb load code tries to use andcc to check the _PAGE_EXEC_4U bit, but that's bit 12 so it gets sign extended all the way up to bit 63 and the test nearly always passes as a result. Use sethi to fix the bug. Signed-off-by: David S. Miller <davem@davemloft.net>
* sparc,sparc64: unify kernel/Sam Ravnborg2008-12-041-0/+552
o Move all files from sparc64/kernel/ to sparc/kernel - rename as appropriate o Update sparc/Makefile to the changes o Update sparc/kernel/Makefile to include the sparc64 files NOTE: This commit changes link order on sparc64! Link order had to change for either of sparc32 and sparc64. And assuming sparc64 see more testing than sparc32 change link order on sparc64 where issues will be caught faster. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: David S. Miller <davem@davemloft.net>