korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-14 07:44:21 +08:00
Code Issues Packages Projects Releases Wiki Activity
14b6320953
linux/arch/sparc/lib/U3copy_from_user.S

28 lines
562 B
ArmAsm
Raw Normal View History

License cleanup: add SPDX GPL-2.0 license identifier to files with no license 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>
2017-11-01 22:07:57 +08:00
/* SPDX-License-Identifier: GPL-2.0 */
Linux-2.6.12-rc2 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!
2005-04-17 06:20:36 +08:00
/* U3copy_from_user.S: UltraSparc-III optimized copy from userspace.
*
* Copyright (C) 1999, 2000, 2004 David S. Miller (davem@redhat.com)
*/
sparc64: Convert U3copy_{from,to}_user to accurate exception reporting. Report the exact number of bytes which have not been successfully copied when an exception occurs, using the running remaining length. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-25 12:20:35 +08:00
#define EX_LD(x,y) \
Linux-2.6.12-rc2 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!
2005-04-17 06:20:36 +08:00
98: x; \
[SPARC64]: Mark __ex_table section correctly. We must use the "a" (allocate) attribute every time we emit an entry into the __ex_table section. For consistency, use "a" instead of #alloc which is some Solaris compat cruft GNU as provides on Sparc. Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-05 15:23:56 +08:00
.section __ex_table,"a";\
Linux-2.6.12-rc2 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!
2005-04-17 06:20:36 +08:00
.align 4; \
sparc64: Convert U3copy_{from,to}_user to accurate exception reporting. Report the exact number of bytes which have not been successfully copied when an exception occurs, using the running remaining length. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-25 12:20:35 +08:00
.word 98b, y; \
Linux-2.6.12-rc2 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!
2005-04-17 06:20:36 +08:00
.text; \
.align 4;
sparc64: Convert U3copy_{from,to}_user to accurate exception reporting. Report the exact number of bytes which have not been successfully copied when an exception occurs, using the running remaining length. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-25 12:20:35 +08:00
#define EX_LD_FP(x,y) \
sparc64: fix FP corruption in user copy functions Short story: Exception handlers used by some copy_to_user() and copy_from_user() functions do not diligently clean up floating point register usage, and this can result in a user process seeing invalid values in floating point registers. This sometimes makes the process fail. Long story: Several cpu-specific (NG4, NG2, U1, U3) memcpy functions use floating point registers and VIS alignaddr/faligndata to accelerate data copying when source and dest addresses don't align well. Linux uses a lazy scheme for saving floating point registers; It is not done upon entering the kernel since it's a very expensive operation. Rather, it is done only when needed. If the kernel ends up not using FP regs during the course of some trap or system call, then it can return to user space without saving or restoring them. The various memcpy functions begin their FP code with VISEntry (or a variation thereof), which saves the FP regs. They conclude their FP code with VISExit (or a variation) which essentially marks the FP regs "clean", ie, they contain no unsaved values. fprs.FPRS_FEF is turned off so that a lazy restore will be triggered when/if the user process accesses floating point regs again. The bug is that the user copy variants of memcpy, copy_from_user() and copy_to_user(), employ an exception handling mechanism to detect faults when accessing user space addresses, and when this handler is invoked, an immediate return from the function is forced, and VISExit is not executed, thus leaving the fprs register in an indeterminate state, but often with fprs.FPRS_FEF set and one or more dirty bits. This results in a return to user space with invalid values in the FP regs, and since fprs.FPRS_FEF is on, no lazy restore occurs. This bug affects copy_to_user() and copy_from_user() for NG4, NG2, U3, and U1. All are fixed by using a new exception handler for those loads and stores that are done during the time between VISEnter and VISExit. n.b. In NG4memcpy, the problematic code can be triggered by a copy size greater than 128 bytes and an unaligned source address. This bug is known to be the cause of random user process memory corruptions while perf is running with the callgraph option (ie, perf record -g). This occurs because perf uses copy_from_user() to read user stacks, and may fault when it follows a stack frame pointer off to an invalid page. Validation checks on the stack address just obscure the underlying problem. Signed-off-by: Rob Gardner <rob.gardner@oracle.com> Signed-off-by: Dave Aldridge <david.j.aldridge@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-23 14:24:49 +08:00
98: x; \
.section __ex_table,"a";\
.align 4; \
sparc64: Convert U3copy_{from,to}_user to accurate exception reporting. Report the exact number of bytes which have not been successfully copied when an exception occurs, using the running remaining length. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-25 12:20:35 +08:00
.word 98b, y##_fp; \
sparc64: fix FP corruption in user copy functions Short story: Exception handlers used by some copy_to_user() and copy_from_user() functions do not diligently clean up floating point register usage, and this can result in a user process seeing invalid values in floating point registers. This sometimes makes the process fail. Long story: Several cpu-specific (NG4, NG2, U1, U3) memcpy functions use floating point registers and VIS alignaddr/faligndata to accelerate data copying when source and dest addresses don't align well. Linux uses a lazy scheme for saving floating point registers; It is not done upon entering the kernel since it's a very expensive operation. Rather, it is done only when needed. If the kernel ends up not using FP regs during the course of some trap or system call, then it can return to user space without saving or restoring them. The various memcpy functions begin their FP code with VISEntry (or a variation thereof), which saves the FP regs. They conclude their FP code with VISExit (or a variation) which essentially marks the FP regs "clean", ie, they contain no unsaved values. fprs.FPRS_FEF is turned off so that a lazy restore will be triggered when/if the user process accesses floating point regs again. The bug is that the user copy variants of memcpy, copy_from_user() and copy_to_user(), employ an exception handling mechanism to detect faults when accessing user space addresses, and when this handler is invoked, an immediate return from the function is forced, and VISExit is not executed, thus leaving the fprs register in an indeterminate state, but often with fprs.FPRS_FEF set and one or more dirty bits. This results in a return to user space with invalid values in the FP regs, and since fprs.FPRS_FEF is on, no lazy restore occurs. This bug affects copy_to_user() and copy_from_user() for NG4, NG2, U3, and U1. All are fixed by using a new exception handler for those loads and stores that are done during the time between VISEnter and VISExit. n.b. In NG4memcpy, the problematic code can be triggered by a copy size greater than 128 bytes and an unaligned source address. This bug is known to be the cause of random user process memory corruptions while perf is running with the callgraph option (ie, perf record -g). This occurs because perf uses copy_from_user() to read user stacks, and may fault when it follows a stack frame pointer off to an invalid page. Validation checks on the stack address just obscure the underlying problem. Signed-off-by: Rob Gardner <rob.gardner@oracle.com> Signed-off-by: Dave Aldridge <david.j.aldridge@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-23 14:24:49 +08:00
.text; \
.align 4;
Linux-2.6.12-rc2 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!
2005-04-17 06:20:36 +08:00
#define FUNC_NAME U3copy_from_user
#define LOAD(type,addr,dest) type##a [addr] %asi, dest
#define EX_RETVAL(x) 0
#include "U3memcpy.S"
Reference in New Issue Copy Permalink