linux/arch/mips/kernel/unaligned.c, branch v4.9

tree-wide: replace config_enabled() with IS_ENABLED()

2016-08-04T12:50:07Z

The use of config_enabled() against config options is ambiguous. In practical terms, config_enabled() is equivalent to IS_BUILTIN(), but the author might have used it for the meaning of IS_ENABLED(). Using IS_ENABLED(), IS_BUILTIN(), IS_MODULE() etc. makes the intention clearer. This commit replaces config_enabled() with IS_ENABLED() where possible. This commit is only touching bool config options. I noticed two cases where config_enabled() is used against a tristate option: - config_enabled(CONFIG_HWMON) [ drivers/net/wireless/ath/ath10k/thermal.c ] - config_enabled(CONFIG_BACKLIGHT_CLASS_DEVICE) [ drivers/gpu/drm/gma500/opregion.c ] I did not touch them because they should be converted to IS_BUILTIN() in order to keep the logic, but I was not sure it was the authors' intention. Link: http://lkml.kernel.org/r/1465215656-20569-1-git-send-email-yamada.masahiro@socionext.com Signed-off-by: Masahiro Yamada Acked-by: Kees Cook Cc: Stas Sergeev Cc: Matt Redfearn Cc: Joshua Kinard Cc: Jiri Slaby Cc: Bjorn Helgaas Cc: Borislav Petkov Cc: Markos Chandras Cc: "Dmitry V. Levin" Cc: yu-cheng yu Cc: James Hogan Cc: Brian Gerst Cc: Johannes Berg Cc: Peter Zijlstra Cc: Al Viro Cc: Will Drewry Cc: Nikolay Martynov Cc: Huacai Chen Cc: "H. Peter Anvin" Cc: Thomas Gleixner Cc: Daniel Borkmann Cc: Leonid Yegoshin Cc: Rafal Milecki Cc: James Cowgill Cc: Greg Kroah-Hartman Cc: Ralf Baechle Cc: Alex Smith Cc: Adam Buchbinder Cc: Qais Yousef Cc: Jiang Liu Cc: Mikko Rapeli Cc: Paul Gortmaker Cc: Denys Vlasenko Cc: Brian Norris Cc: Hidehiro Kawai Cc: "Luis R. Rodriguez" Cc: Andy Lutomirski Cc: Ingo Molnar Cc: Dave Hansen Cc: "Kirill A. Shutemov" Cc: Roland McGrath Cc: Paul Burton Cc: Kalle Valo Cc: Viresh Kumar Cc: Tony Wu Cc: Huaitong Han Cc: Sumit Semwal Cc: Alexei Starovoitov Cc: Juergen Gross Cc: Jason Cooper Cc: "David S. Miller" Cc: Oleg Nesterov Cc: Andrea Gelmini Cc: David Woodhouse Cc: Marc Zyngier Cc: Rabin Vincent Cc: "Maciej W. Rozycki" Cc: David Daney Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

MIPS: Allow emulation for unaligned [LS]DXC1 instructions

2016-05-13T13:30:25Z

If an address error exception occurs for a LDXC1 or SDXC1 instruction, within the cop1x opcode space, allow it to be passed through to the FPU emulator rather than resulting in a SIGILL. This causes LDXC1 & SDXC1 to be handled in a manner consistent with the more common LDC1 & SDC1 instructions. Signed-off-by: Paul Burton Tested-by: Aurelien Jarno Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/13143/ Signed-off-by: Ralf Baechle

MIPS: Fix MSA ld unaligned failure cases

2016-03-29T12:18:18Z

Copying the content of an MSA vector from user memory may involve TLB faults & mapping in pages. This will fail when preemption is disabled due to an inability to acquire mmap_sem from do_page_fault, which meant such vector loads to unmapped pages would always fail to be emulated. Fix this by disabling preemption later only around the updating of vector register state. This change does however introduce a race between performing the load into thread context & the thread being preempted, saving its current live context & clobbering the loaded value. This should be a rare occureence, so optimise for the fast path by simply repeating the load if we are preempted. Additionally if the copy failed then the failure path was taken with preemption left disabled, leading to the kernel typically encountering further issues around sleeping whilst atomic. The change to where preemption is disabled avoids this issue. Fixes: e4aa1f153add "MIPS: MSA unaligned memory access support" Reported-by: James Hogan Signed-off-by: Paul Burton Reviewed-by: James Hogan Cc: Leonid Yegoshin Cc: Maciej W. Rozycki Cc: James Cowgill Cc: Markos Chandras Cc: stable # v4.3 Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/12345/ Signed-off-by: Ralf Baechle

MIPS: Declare mips_debugfs_dir in a header

2015-10-26T08:49:42Z

We have many extern declarations of mips_debugfs_dir through arch/mips/ in various C files. Unify them by declaring mips_debugfs_dir in a header, including it in each affected C file & removing the duplicate declarations. Signed-off-by: Paul Burton Cc: linux-mips@linux-mips.org Cc: Steven J. Hill Cc: Alexander Sverdlin Cc: Masahiro Yamada Cc: Leonid Yegoshin Cc: Maciej W. Rozycki Cc: linux-kernel@vger.kernel.org Cc: Joe Perches Cc: Jaedon Shin Cc: James Hogan Cc: David Daney Cc: Zubair Lutfullah Kakakhel Cc: Markos Chandras Cc: James Cowgill Patchwork: https://patchwork.linux-mips.org/patch/11181/ Signed-off-by: Ralf Baechle

MIPS: unaligned: Move from deprecated __initcall to arch_initcall.

2015-09-03T10:07:49Z

Signed-off-by: Ralf Baechle

MIPS: MSA unaligned memory access support

2015-09-03T10:07:40Z

The MSA architecture specification allows for hardware to not implement unaligned vector memory accesses in some or all cases. A typical example of this is the I6400 core which does not implement unaligned vector memory access when the memory crosses a page boundary. The architecture also requires that such memory accesses complete successfully as far as userland is concerned, so the kernel is required to emulate them. This patch implements support for emulating unaligned MSA ld & st instructions by copying between the user memory & the tasks FP context in struct thread_struct, updating hardware registers from there as appropriate in order to avoid saving & restoring the entire vector context for each unaligned memory access. Tested both using an I6400 CPU and with a QEMU build hacked to produce AdEL exceptions for unaligned vector memory accesses. [paul.burton@imgtec.com: - Remove #ifdef's - Move msa_op into enum major_op rather than #define - Replace msa_{to,from}_wd with {read,write}_msa_wr_{b,h,w,l} and the format-agnostic wrappers, removing the custom endian mangling for big endian systems. - Restructure the msa_op case in emulate_load_store_insn to share more code between the load & store cases. - Avoid the need for a temporary union fpureg on the stack by simply reusing the already suitably aligned context in struct thread_struct. - Use sizeof(*fpr) rather than hardcoding 16 as the size for user memory checks & copies. - Stop recalculating the address of the unaligned vector memory access and rely upon the value read from BadVAddr as we do for other unaligned memory access instructions. - Drop the now unused val8 & val16 fields in union fpureg. - Rewrite commit message. - General formatting cleanups.] Signed-off-by: Paul Burton Cc: linux-mips@linux-mips.org Cc: Leonid Yegoshin Cc: Huacai Chen Cc: Maciej W. Rozycki Cc: linux-kernel@vger.kernel.org Cc: Jie Chen Cc: Markos Chandras Patchwork: https://patchwork.linux-mips.org/patch/10573/ Signed-off-by: Ralf Baechle

MIPS: unaligned: Fix build error on big endian R6 kernels

2015-08-03T07:25:05Z

Commit eeb538950367 ("MIPS: unaligned: Prevent EVA instructions on kernel unaligned accesses") renamed the Load* and Store* defines in unaligned.c to _Load* and _Store* as part of its fix. One define was missed out which causes big endian R6 kernels to fail to build. arch/mips/kernel/unaligned.c:880:35: error: implicit declaration of function '_StoreDW' #define StoreDW(addr, value, res) _StoreDW(addr, value, res) ^ Signed-off-by: James Cowgill Fixes: eeb538950367 ("MIPS: unaligned: Prevent EVA instructions on kernel unaligned accesses") Cc: Markos Chandras Cc: # 4.0+ Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/10575/ Signed-off-by: Ralf Baechle

Merge branch '4.0-fixes' into mips-for-linux-next

2015-04-13T14:03:32Z

MIPS: unaligned: Fix regular load/store instruction emulation for EVA

2015-04-10T13:41:45Z

When emulating a regular lh/lw/lhu/sh/sw we need to use the appropriate instruction if we are in EVA mode. This is necessary for userspace applications which trigger alignment exceptions. In such case, the userspace load/store instruction needs to be emulated with the correct eva/non-eva instruction by the kernel emulator. Signed-off-by: Markos Chandras Fixes: c1771216ab48 ("MIPS: kernel: unaligned: Handle unaligned accesses for EVA") Cc: # v3.15+ Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9503/ Signed-off-by: Ralf Baechle

MIPS: unaligned: Surround load/store macros in do {} while statements

2015-04-10T13:41:44Z

It's best to surround such complex macros with do {} while statements so they can appear as independent logical blocks when used within other control blocks. Signed-off-by: Markos Chandras Cc: # v3.15+ Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9502/ Signed-off-by: Ralf Baechle