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* ARC: mm: support 4 levels of page tablesVineet Gupta2021-08-261-0/+11
| | | | | Acked-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Vineet Gupta <vgupta@kernel.org>
* ARC: mm: support 3 levels of page tablesVineet Gupta2021-08-261-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ARCv2 MMU is software walked and Linux implements 2 levels of paging: pgd/pte. Forthcoming hw will have multiple levels, so this change preps mm code for same. It is also fun to try multi levels even on soft-walked code to ensure generic mm code is robust to handle. overview ________ 2 levels {pgd, pte} : pmd is folded but pmd_* macros are valid and operate on pgd 3 levels {pgd, pmd, pte}: - pud is folded and pud_* macros point to pgd - pmd_* macros operate on actual pmd code changes ____________ 1. #include <asm-generic/pgtable-nopud.h> 2. Define CONFIG_PGTABLE_LEVELS 3 3a. Define PMD_SHIFT, PMD_SIZE, PMD_MASK, pmd_t 3b. Define pmd_val() which actually deals with pmd (pmd_offset(), pmd_index() are provided by generic code) 3c. pmd_alloc_one()/pmd_free() also provided by generic code (pmd_populate/pmd_free already exist) 4. Define pud_none(), pud_bad() macros based on generic pud_val() which internally pertains to pgd now. 4b. define pud_populate() to just setup pgd Acked-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Vineet Gupta <vgupta@kernel.org>
* ARC: mm: switch pgtable_t back to struct page *Vineet Gupta2021-08-261-1/+1
| | | | | | | | | | | | | | | | | So far ARC pgtable_t has not been struct page based to avoid extra page_address() calls involved. However the differences are down to noise and get in the way of using generic code, hence this patch. This also allows us to reuse generic THP depost/withdraw code. There's some additional consideration for PGDIR_SHIFT in 4K page config. Now due to page tables being PAGE_SIZE deep only, the address split can't be really arbitrary. Tested-by: kernel test robot <lkp@intel.com> Suggested-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Vineet Gupta <vgupta@kernel.org>
* ARC: mm: non-functional code movement/cleanupVineet Gupta2021-08-241-14/+16
| | | | Signed-off-by: Vineet Gupta <vgupta@kernel.org>
* ARC: mm: Enable STRICT_MM_TYPECHECKSVineet Gupta2021-08-241-26/+0
| | | | | | | | | | | | | | | | | | | | | In the past I've refrained from doing this (at least 2 times) due to the slight code bloat due to ABI implications of pte_t etc becoming struct Per ARC ABI, functions return struct via memory and not through register r0, even if the struct would fit in register(s) - caller allocates space on stack and passes the address as first arg (r0), shifting rest of args by one - callee creates return struct in memory (referenced via r0) This time around the code actually shrunk slightly (due to subtle inlining heuristic effects), but still slightly inefficient due to return values passed through memory. That however seems like a small cost compared to maintenance burden given the impending new mmu support for page walk etc Signed-off-by: Vineet Gupta <vgupta@kernel.org>
* ARC: mm: PAE: use 40-bit physical page maskVladimir Isaev2021-05-101-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | 32-bit PAGE_MASK can not be used as a mask for physical addresses when PAE is enabled. PAGE_MASK_PHYS must be used for physical addresses instead of PAGE_MASK. Without this, init gets SIGSEGV if pte_modify was called: | potentially unexpected fatal signal 11. | Path: /bin/busybox | CPU: 0 PID: 1 Comm: init Not tainted 5.12.0-rc5-00003-g1e43c377a79f-dirty | Insn could not be fetched | @No matching VMA found | ECR: 0x00040000 EFA: 0x00000000 ERET: 0x00000000 | STAT: 0x80080082 [IE U ] BTA: 0x00000000 | SP: 0x5f9ffe44 FP: 0x00000000 BLK: 0xaf3d4 | LPS: 0x000d093e LPE: 0x000d0950 LPC: 0x00000000 | r00: 0x00000002 r01: 0x5f9fff14 r02: 0x5f9fff20 | ... | Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b Signed-off-by: Vladimir Isaev <isaev@synopsys.com> Reported-by: kernel test robot <lkp@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: stable@vger.kernel.org Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* arch/arc: add copy_user_page() to <asm/page.h> to fix build error on ARCRandy Dunlap2021-01-051-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | fs/dax.c uses copy_user_page() but ARC does not provide that interface, resulting in a build error. Provide copy_user_page() in <asm/page.h>. ../fs/dax.c: In function 'copy_cow_page_dax': ../fs/dax.c:702:2: error: implicit declaration of function 'copy_user_page'; did you mean 'copy_to_user_page'? [-Werror=implicit-function-declaration] Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: linux-snps-arc@lists.infradead.org Cc: Dan Williams <dan.j.williams@intel.com> #Acked-by: Vineet Gupta <vgupta@synopsys.com> # v1 Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Jan Kara <jack@suse.cz> Cc: linux-fsdevel@vger.kernel.org Cc: linux-nvdimm@lists.01.org #Reviewed-by: Ira Weiny <ira.weiny@intel.com> # v2 Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* arc: use FLATMEM with freeing of unused memory map instead of DISCONTIGMEMMike Rapoport2020-12-151-3/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently ARC uses DISCONTIGMEM to cope with sparse physical memory address space on systems with 2 memory banks. While DISCONTIGMEM avoids wasting memory on unpopulated memory map, it adds both memory and CPU overhead relatively to FLATMEM. Moreover, DISCONTINGMEM is generally considered deprecated. The obvious replacement for DISCONTIGMEM would be SPARSEMEM, but it is also less efficient than FLATMEM in pfn_to_page() and page_to_pfn() conversions. Besides it requires tuning of SECTION_SIZE which is not trivial for possible ARC memory configuration. Since the memory map for both banks is always allocated from the "lowmem" bank, it is possible to use FLATMEM for two-bank configuration and simply free the unused hole in the memory map. All is required for that is to provide ARC-specific pfn_valid() that will take into account actual physical memory configuration and define HAVE_ARCH_PFN_VALID. The resulting kernel image configured with defconfig + HIGHMEM=y is smaller: $ size a/vmlinux b/vmlinux text data bss dec hex filename 4673503 1245456 279756 6198715 5e95bb a/vmlinux 4658706 1246864 279756 6185326 5e616e b/vmlinux $ ./scripts/bloat-o-meter a/vmlinux b/vmlinux add/remove: 28/30 grow/shrink: 42/399 up/down: 10986/-29025 (-18039) ... Total: Before=4709315, After = 4691276, chg -0.38% Booting nSIM with haps_ns.dts results in the following memory usage reports: a: Memory: 1559104K/1572864K available (3531K kernel code, 595K rwdata, 752K rodata, 136K init, 275K bss, 13760K reserved, 0K cma-reserved, 1048576K highmem) b: Memory: 1559112K/1572864K available (3519K kernel code, 594K rwdata, 752K rodata, 136K init, 280K bss, 13752K reserved, 0K cma-reserved, 1048576K highmem) Link: https://lkml.kernel.org/r/20201101170454.9567-11-rppt@kernel.org Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matt Turner <mattst88@gmail.com> Cc: Meelis Roos <mroos@linux.ee> Cc: Michael Schmitz <schmitzmic@gmail.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/vma: define a default value for VM_DATA_DEFAULT_FLAGSAnshuman Khandual2020-04-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are many platforms with exact same value for VM_DATA_DEFAULT_FLAGS This creates a default value for VM_DATA_DEFAULT_FLAGS in line with the existing VM_STACK_DEFAULT_FLAGS. While here, also define some more macros with standard VMA access flag combinations that are used frequently across many platforms. Apart from simplification, this reduces code duplication as well. Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mark Salter <msalter@redhat.com> Cc: Guo Ren <guoren@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Brian Cain <bcain@codeaurora.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paulburton@kernel.org> Cc: Nick Hu <nickhu@andestech.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Rich Felker <dalias@libc.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jeff Dike <jdike@addtoit.com> Cc: Chris Zankel <chris@zankel.net> Link: http://lkml.kernel.org/r/1583391014-8170-2-git-send-email-anshuman.khandual@arm.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner2019-06-191-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ARC: mm: allow mprotect to make stack mappings executableVineet Gupta2018-07-111-1/+1
| | | | | | | | | | | | | | | | | | | | | mprotect(EXEC) was failing for stack mappings as default vm flags was missing MAYEXEC. This was triggered by glibc test suite nptl/tst-execstack testcase What is surprising is that despite running LTP for years on, we didn't catch this issue as it lacks a directed test case. gcc dejagnu tests with nested functions also requiring exec stack work fine though because they rely on the GNU_STACK segment spit out by compiler and handled in kernel elf loader. This glibc case is different as the stack is non exec to begin with and a dlopen of shared lib with GNU_STACK segment triggers the exec stack proceedings using a mprotect(PROT_EXEC) which was broken. CC: stable@vger.kernel.org Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: mm: Decouple RAM base address from kernel link addressEugeniy Paltsev2017-09-011-1/+1
| | | | | | | | | | | | | | | | | | [Needed for HSDK] Currently the first page of system (hence RAM base) is assumed to be @ CONFIG_LINUX_LINK_BASE, where kernel itself is linked. However is case of HSDK platform, for reasons explained in that patch, this is not true. kernel needs to be linked @ 0x9000_0000 while DDR is still wired at 0x8000_0000. To properly account for this 256M of RAM, we need to introduce a new option and base page frame accountiing off of it. Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> [vgupta: renamed CONFIG_KERNEL_RAM_BASE_ADDRESS => CONFIG_LINUX_RAM_BASE : simplified changelog]
* ARC: pae: STRICT_MM_TYPECHECKS was brokenVineet Gupta2016-05-131-0/+4
| | | | Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: support HIGHMEM even without PAE40Vineet Gupta2016-05-051-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Initial HIGHMEM support on ARC was introduced for PAE40 where the low memory (0x8000_0000 based) and high memory (0x1_0000_0000) were physically contiguous. So CONFIG_FLATMEM sufficed (despite a peipheral hole in the middle, which wasted a bit of struct page memory, but things worked). However w/o PAE, highmem was not possible and we could only reach ~1.75GB of DDR. Now there is a use case to access ~4GB of DDR w/o PAE40 The idea is to have low memory at canonical 0x8000_0000 and highmem at 0 so enire 4GB address space is available for physical addressing This needs additional platform/interconnect mapping to convert the non contiguous physical addresses into linear bus adresses. From Linux point of view, non contiguous divide means FLATMEM no longer works and DISCONTIGMEM is needed to track the pfns in the 2 regions. This scheme would also work for PAE40, only better in that we don't waste struct page memory for the peripheral hole. The DT description will be something like memory { ... reg = <0x80000000 0x200000000 /* 512MB: lowmem */ 0x00000000 0x10000000>; /* 256MB: highmem */ } Signed-off-by: Noam Camus <noamc@ezchip.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: Fix PAE40 boot failures due to PTE truncationVineet Gupta2016-05-051-1/+8
| | | | | | | | | | | | | | | So a benign looking cleanup which macro'ized PAGE_SHIFT shifts turned out to be bad (since it was done non-sensically across the board). It caused boot failures with PAE40 as forced cast to (unsigned long) from newly introduced virt_to_pfn() was causing truncatiion of the (long long) pte/paddr values. It is OK to use this in accessors dealing with kernel virtual address, pointers etc, but not for PTE values themelves. Fixes: cJ2ff5cf2735c ("ARC: mm: Use virt_to_pfn() for addr >> PAGE_SHIFT pattern) Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* Merge tag 'asm-generic-4.6' of ↵Linus Torvalds2016-03-241-3/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic updates from Arnd Bergmann: "There are only three patches this time, most other changes to files in include/asm-generic tend to go through the tree of whoever depends on the change. Two patches are cleanups for stuff that is no longer needed, the main change is to adapt the generic version of BUG_ON() for CONFIG_BUG=n to make it behave consistently with BUG(). This avoids undefined behavior along with a number of warnings about that undefined behavior in randconfig builds when we keep going on after hitting a BUG_ON()" * tag 'asm-generic-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: asm-generic: remove old nonatomic-io wrapper files asm-generic: default BUG_ON(x) to if(x)BUG() asm-generic: page.h: Remove useless get_user_page and free_user_page
| * asm-generic: page.h: Remove useless get_user_page and free_user_pageChen Gang2016-02-261-3/+0
| | | | | | | | | | | | | | | | | | | | | | They are not symmetric with each other, neither are used in real world (can not be found by grep command in source code root directory), so remove them. Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
* | ARC: mm: Use virt_to_pfn() for addr >> PAGE_SHIFT patternVineet Gupta2016-03-121-12/+7
|/ | | | Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: mm: PAE40 supportVineet Gupta2015-10-291-0/+4
| | | | | | | | This is the first working implementation of 40-bit physical address extension on ARCv2. Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARCv2: mm: THP supportVineet Gupta2015-10-171-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | MMUv4 in HS38x cores supports Super Pages which are basis for Linux THP support. Normal and Super pages can co-exist (ofcourse not overlap) in TLB with a new bit "SZ" in TLB page desciptor to distinguish between them. Super Page size is configurable in hardware (4K to 16M), but fixed once RTL builds. The exact THP size a Linx configuration will support is a function of: - MMU page size (typical 8K, RTL fixed) - software page walker address split between PGD:PTE:PFN (typical 11:8:13, but can be changed with 1 line) So for above default, THP size supported is 8K * 256 = 2M Default Page Walker is 2 levels, PGD:PTE:PFN, which in THP regime reduces to 1 level (as PTE is folded into PGD and canonically referred to as PMD). Thus thp PMD accessors are implemented in terms of PTE (just like sparc) Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: mm: switch pgtable_to to pte_t *Vineet Gupta2015-10-091-2/+2
| | | | | | | | | | | | ARC is the only arch with unsigned long type (vs. struct page *). Historically this was done to avoid the page_address() calls in various arch hooks which need to get the virtual/logical address of the table. Some arches alternately define it as pte_t *, and is as efficient as unsigned long (generated code doesn't change) Suggested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: [mm] Make stack/heap Non-executable by defaultVineet Gupta2013-06-221-6/+1
| | | | | | | | | | | | | | | | 1. For VM_EXEC based delayed dcache/icache flush, reduces the number of flushes. 2. Makes this security feature ON by default rather than OFF before. 3. Applications can use mprotect() to selectively override this. 4. ELF binaries have a GNU_STACK segment which can easily override the kernel default permissions. For nested-functions/trampolines, gcc already auto-enables executable stack in elf. Others needing this can use -Wl,-z,execstack option. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: lazy dcache flush broke gdb in non-aliasing configsVineet Gupta2013-05-251-9/+0
| | | | | | | | | | | | | gdbserver inserting a breakpoint ends up calling copy_user_page() for a code page. The generic version of which (non-aliasing config) didn't set the PG_arch_1 bit hence update_mmu_cache() didn't sync dcache/icache for corresponding dynamic loader code page - causing garbade to be executed. So now aliasing versions of copy_user_highpage()/clear_page() are made default. There is no significant overhead since all of special alias handling code is compiled out for non-aliasing build Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: [mm] Aliasing VIPT dcache support 2/4Vineet Gupta2013-05-091-1/+15
| | | | | | | | | | | | | | | | | | | | | | | This is the meat of the series which prevents any dcache alias creation by always keeping the U and K mapping of a page congruent. If a mapping already exists, and other tries to access the page, prev one is flushed to physical page (wback+inv) Essentially flush_dcache_page()/copy_user_highpage() create K-mapping of a page, but try to defer flushing, unless U-mapping exist. When page is actually mapped to userspace, update_mmu_cache() flushes the K-mapping (in certain cases this can be optimised out) Additonally flush_cache_mm(), flush_cache_range(), flush_cache_page() handle the puring of stale userspace mappings on exit/munmap... flush_anon_page() handles the existing U-mapping for anon page before kernel reads it via the GUP path. Note that while not complete, this is enough to boot a simple dynamically linked Busybox based rootfs Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: Add support for ioremap_prot APIGilad Ben-Yossef2013-02-151-0/+3
| | | | | | | | | | | | | | | | | | | Implement ioremap_prot() to allow mapping IO memory with variable protection via TLB. Implementing this allows the /dev/mem driver to use its generic access() VMA callback, which in turn allows ptrace to examine data in memory mapped regions mapped via /dev/mem, such as Arc DCCM. The end result is that it is possible to examine values of variables placed into DCCM in user space programs via GDB. CC: Alexey Brodkin <Alexey.Brodkin@synopsys.com> CC: Noam Camus <noamc@ezchip.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: UAPI Disintegrate arch/arc/include/asmVineet Gupta2013-02-151-29/+1
| | | | | | | | | | | | | | | | | | | | 1. ./genfilelist.pl arch/arc/include/asm/ 2. Create arch/arc/include/uapi/asm/Kbuild as follows +# UAPI Header export list +include include/uapi/asm-generic/Kbuild.asm 3. ./disintegrate-one.pl arch/arc/include/{,uapi/}asm/<above-list> 4. Edit arch/arc/include/asm/Kbuild to remove ref to asm-generic/Kbuild.asm - To work around empty uapi/asm/setup.h added a placholder comment. - Also a manual #ifdef __ASSEMBLY__ for a late ptrace change Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: David Howells <dhowells@redhat.com>
* ARC: Page Table ManagementVineet Gupta2013-02-151-0/+92
| | | | Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
* ARC: Fundamental ARCH data-types/definesVineet Gupta2013-02-111-0/+42
* L1_CACHE_SHIFT * PAGE_SIZE, PAGE_OFFSET * struct pt_regs, struct user_regs_struct * struct thread_struct, cpu_relax(), task_pt_regs(), start_thread(), ... * struct thread_info, THREAD_SIZE, INIT_THREAD_INFO(), TIF_*, ... * BUG() * ELF_* * Elf_* To disallow user-space visibility into some of the core kernel data-types such as struct pt_regs, #ifdef __KERNEL__ which also makes the UAPI header spit (further patch in the series) to NOT export it to asm/uapi/ptrace.h Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Jonas Bonn <jonas.bonn@gmail.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Acked-by: Arnd Bergmann <arnd@arndb.de>