kernel/linux.git/arch/arm/mm/idmap.c, branch linux-4.16.y

ARM: 8734/1: mm: idmap: Mark variables as ro_after_init

2017-12-17T22:16:20+00:00

idmap_pgd, arch_phys_to_idmap_offset are setup once while init stage, and never changed after that. so, it is good candidate for __ro_after_init. Reviewed-by: Kees Cook Signed-off-by: Jinbum Park Signed-off-by: Russell King

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55+00:00

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 Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

sched/headers: Prepare to remove the dependency from

2017-03-02T07:42:37+00:00

Update code that relied on sched.h including various MM types for them. This will allow us to remove the include from . Acked-by: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar

ARM: provide improved virt_to_idmap() functionality

2016-05-03T10:13:54+00:00

For kexec, we need more functionality from the IDMAP system. We need to be able to convert physical addresses to their identity mappped versions as well as virtual addresses. Convert the existing arch_virt_to_idmap() to deal with physical addresses instead. Acked-by: Santosh Shilimkar Signed-off-by: Russell King

ARM: make virt_to_idmap() return unsigned long

2016-02-08T15:47:28+00:00

Make virt_to_idmap() return an unsigned long rather than phys_addr_t. Returning phys_addr_t here makes no sense, because the definition of virt_to_idmap() is that it shall return a physical address which maps identically with the virtual address. Since virtual addresses are limited to 32-bit, identity mapped physical addresses are as well. Almost all users already had an implicit narrowing cast to unsigned long so let's make this official and part of this interface. Tested-by: Grygorii Strashko Signed-off-by: Russell King

ARM: make xscale iwmmxt code multiplatform aware

2015-12-01T20:44:24+00:00

In a multiplatform configuration, we may end up building a kernel for both Marvell PJ1 and an ARMv4 CPU implementation. In that case, the xscale-cp0 code is built with gcc -march=armv4{,t}, which results in a build error from the coprocessor instructions. Since we know this code will only have to run on an actual xscale processor, we can simply build the entire file for ARMv5TE. Related to this, we need to handle the iWMMXT initialization sequence differently during boot, to ensure we don't try to touch xscale specific registers on other CPUs from the xscale_cp0_init initcall. cpu_is_xscale() used to be hardcoded to '1' in any configuration that enables any XScale-compatible core, but this breaks once we can have a combined kernel with MMP1 and something else. In this patch, I replace the existing cpu_is_xscale() macro with a new cpu_is_xscale_family() macro that evaluates true for xscale, xsc3 and mohawk, which makes the behavior more deterministic. The two existing users of cpu_is_xscale() are modified accordingly, but slightly change behavior for kernels that enable CPU_MOHAWK without also enabling CPU_XSCALE or CPU_XSC3. Previously, these would leave leave PMD_BIT4 in the page tables untouched, now they clear it as we've always done for kernels that enable both MOHAWK and the support for the older CPU types. Since the previous behavior was inconsistent, I assume it was unintentional. Signed-off-by: Arnd Bergmann

ARM: 8152/1: Convert pr_warning to pr_warn

2014-09-26T13:39:53+00:00

Use the more common pr_warn. Other miscellanea: o Coalesce formats o Realign arguments Signed-off-by: Joe Perches Signed-off-by: Russell King

ARM: idmap: add identity mapping usage note

2014-08-02T14:20:26+00:00

Add a note about the usage of the identity mapping; we do not support accesses outside of the identity map region and kernel image while a CPU is using the identity map. This is because the identity mapping may overwrite vmalloc space, IO mappings, the vectors pages, etc. Acked-by: Will Deacon Signed-off-by: Russell King

ARM: 8115/1: LPAE: reduce damage caused by idmap to virtual memory layout

2014-07-29T12:00:04+00:00

On LPAE, each level 1 (pgd) page table entry maps 1GiB, and the level 2 (pmd) entries map 2MiB. When the identity mapping is created on LPAE, the pgd pointers are copied from the swapper_pg_dir. If we find that we need to modify the contents of a pmd, we allocate a new empty pmd table and insert it into the appropriate 1GB slot, before then filling it with the identity mapping. However, if the 1GB slot covers the kernel lowmem mappings, we obliterate those mappings. When replacing a PMD, first copy the old PMD contents to the new PMD, so that we preserve the existing mappings, particularly the mappings of the kernel itself. [rewrote commit message and added code comment -- rmk] Fixes: ae2de101739c ("ARM: LPAE: Add identity mapping support for the 3-level page table format") Signed-off-by: Konstantin Khlebnikov Signed-off-by: Russell King

ARM: mm: Move the idmap print to appropriate place in the code

2013-10-11T00:25:06+00:00

Commit 9e9a367c29cebd2 {ARM: Section based HYP idmap} moved the address conversion inside identity_mapping_add() without respective print which carries useful idmap information. Move the print as well inside identity_mapping_add() to fix the same. Cc: Will Deacon Cc: Nicolas Pitre Cc: Russell King Signed-off-by: Santosh Shilimkar