kernel/linux.git/arch/openrisc, branch linux-5.9.y

sched/idle: Fix arch_cpu_idle() vs tracing

2020-12-16T09:58:32+00:00

[ Upstream commit 58c644ba512cfbc2e39b758dd979edd1d6d00e27 ] We call arch_cpu_idle() with RCU disabled, but then use local_irq_{en,dis}able(), which invokes tracing, which relies on RCU. Switch all arch_cpu_idle() implementations to use raw_local_irq_{en,dis}able() and carefully manage the lockdep,rcu,tracing state like we do in entry. (XXX: we really should change arch_cpu_idle() to not return with interrupts enabled) Reported-by: Sven Schnelle Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Mark Rutland Tested-by: Mark Rutland Link: https://lkml.kernel.org/r/20201120114925.594122626@infradead.org Signed-off-by: Sasha Levin

Merge tag 'for-linus' of git://github.com/openrisc/linux

2020-09-12T20:03:49+00:00

Pull OpenRISC fixes from Stafford Horne: "Fixes for compile issues pointed out by kbuild and one bug I found in initrd with the 5.9 patches" * tag 'for-linus' of git://github.com/openrisc/linux: openrisc: Fix issue with get_user for 64-bit values openrisc: Fix cache API compile issue when not inlining openrisc: Reserve memblock for initrd

openrisc: Fix issue with get_user for 64-bit values

2020-09-12T08:26:00+00:00

A build failure was raised by kbuild with the following error. drivers/android/binder.c: Assembler messages: drivers/android/binder.c:3861: Error: unrecognized keyword/register name `l.lwz ?ap,4(r24)' drivers/android/binder.c:3866: Error: unrecognized keyword/register name `l.addi ?ap,r0,0' The issue is with 64-bit get_user() calls on openrisc. I traced this to a problem where in the internally in the get_user macros there is a cast to long __gu_val this causes GCC to think the get_user call is 32-bit. This binder code is really long and GCC allocates register r30, which triggers the issue. The 64-bit get_user asm tries to get the 64-bit pair register, which for r30 overflows the general register names and returns the dummy register ?ap. The fix here is to move the temporary variables into the asm macros. We use a 32-bit __gu_tmp for 32-bit and smaller macro and a 64-bit tmp in the 64-bit macro. The cast in the 64-bit macro has a trick of casting through __typeof__((x)-(x)) which avoids the below warning. This was barrowed from riscv. arch/openrisc/include/asm/uaccess.h:240:8: warning: cast to pointer from integer of different size I tested this in a small unit test to check reading between 64-bit and 32-bit pointers to 64-bit and 32-bit values in all combinations. Also I ran make C=1 to confirm no new sparse warnings came up. It all looks clean to me. Link: https://lore.kernel.org/lkml/202008200453.ohnhqkjQ%25lkp@intel.com/ Signed-off-by: Stafford Horne Reviewed-by: Luc Van Oostenryck

openrisc: Fix cache API compile issue when not inlining

2020-09-07T12:02:15+00:00

I found this when compiling a kbuild random config with GCC 11. The config enables CONFIG_DEBUG_SECTION_MISMATCH, which sets CFLAGS -fno-inline-functions-called-once. This causes the call to cache_loop in cache.c to not be inlined causing the below compile error. In file included from arch/openrisc/mm/cache.c:13: arch/openrisc/mm/cache.c: In function 'cache_loop': ./arch/openrisc/include/asm/spr.h:16:27: warning: 'asm' operand 0 probably does not match constraints 16 | #define mtspr(_spr, _val) __asm__ __volatile__ ( \ | ^~~~~~~ arch/openrisc/mm/cache.c:25:3: note: in expansion of macro 'mtspr' 25 | mtspr(reg, line); | ^~~~~ ./arch/openrisc/include/asm/spr.h:16:27: error: impossible constraint in 'asm' 16 | #define mtspr(_spr, _val) __asm__ __volatile__ ( \ | ^~~~~~~ arch/openrisc/mm/cache.c:25:3: note: in expansion of macro 'mtspr' 25 | mtspr(reg, line); | ^~~~~ make[1]: *** [scripts/Makefile.build:283: arch/openrisc/mm/cache.o] Error 1 The asm constraint "K" requires a immediate constant argument to mtspr, however because of no inlining a register argument is passed causing a failure. Fix this by using __always_inline. Link: https://lore.kernel.org/lkml/202008200453.ohnhqkjQ%25lkp@intel.com/ Signed-off-by: Stafford Horne

openrisc: Reserve memblock for initrd

2020-09-07T12:01:46+00:00

Recently OpenRISC added support for external initrd images, but I found some instability when using larger buildroot initrd images. It turned out that I forgot to reserve the memblock space for the initrd image. This patch fixes the instability issue by reserving memblock space. Fixes: ff6c923dbec3 ("openrisc: Add support for external initrd images") Signed-off-by: Stafford Horne Reviewed-by: Mike Rapoport

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59+00:00

Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva

Merge tag 'for-linus' of git://github.com/openrisc/linux

2020-08-14T21:04:53+00:00

Pull OpenRISC updates from Stafford Horne: "A few patches all over the place during this cycle, mostly bug and sparse warning fixes for OpenRISC, but a few enhancements too. Note, there are 2 non OpenRISC specific fixups. Non OpenRISC fixes: - In init we need to align the init_task correctly to fix an issue with MUTEX_FLAGS, reviewed by Peter Z. No one picked this up so I kept it on my tree. - In asm-generic/io.h I fixed up some sparse warnings, OK'd by Arnd. Arnd asked to merge it via my tree. OpenRISC fixes: - Many fixes for OpenRISC sprase warnings. - Add support OpenRISC SMP tlb flushing rather than always flushing the entire TLB on every CPU. - Fix bug when dumping stack via /proc/xxx/stack of user threads" * tag 'for-linus' of git://github.com/openrisc/linux: openrisc: uaccess: Add user address space check to access_ok openrisc: signal: Fix sparse address space warnings openrisc: uaccess: Remove unused macro __addr_ok openrisc: uaccess: Use static inline function in access_ok openrisc: uaccess: Fix sparse address space warnings openrisc: io: Fixup defines and move include to the end asm-generic/io.h: Fix sparse warnings on big-endian architectures openrisc: Implement proper SMP tlb flushing openrisc: Fix oops caused when dumping stack openrisc: Add support for external initrd images init: Align init_task to avoid conflict with MUTEX_FLAGS openrisc: fix __user in raw_copy_to_user()'s prototype

mm/openrisc: use general page fault accounting

2020-08-12T17:58:03+00:00

Use the general page fault accounting by passing regs into handle_mm_fault(). It naturally solve the issue of multiple page fault accounting when page fault retry happened. Add the missing PERF_COUNT_SW_PAGE_FAULTS perf events too. Note, the other two perf events (PERF_COUNT_SW_PAGE_FAULTS_[MAJ|MIN]) were done in handle_mm_fault(). Signed-off-by: Peter Xu Signed-off-by: Andrew Morton Acked-by: Stafford Horne Cc: Jonas Bonn Cc: Stefan Kristiansson Link: http://lkml.kernel.org/r/20200707225021.200906-15-peterx@redhat.com Signed-off-by: Linus Torvalds

mm: do page fault accounting in handle_mm_fault

2020-08-12T17:58:02+00:00

Patch series "mm: Page fault accounting cleanups", v5. This is v5 of the pf accounting cleanup series. It originates from Gerald Schaefer's report on an issue a week ago regarding to incorrect page fault accountings for retried page fault after commit 4064b9827063 ("mm: allow VM_FAULT_RETRY for multiple times"): https://lore.kernel.org/lkml/20200610174811.44b94525@thinkpad/ What this series did: - Correct page fault accounting: we do accounting for a page fault (no matter whether it's from #PF handling, or gup, or anything else) only with the one that completed the fault. For example, page fault retries should not be counted in page fault counters. Same to the perf events. - Unify definition of PERF_COUNT_SW_PAGE_FAULTS: currently this perf event is used in an adhoc way across different archs. Case (1): for many archs it's done at the entry of a page fault handler, so that it will also cover e.g. errornous faults. Case (2): for some other archs, it is only accounted when the page fault is resolved successfully. Case (3): there're still quite some archs that have not enabled this perf event. Since this series will touch merely all the archs, we unify this perf event to always follow case (1), which is the one that makes most sense. And since we moved the accounting into handle_mm_fault, the other two MAJ/MIN perf events are well taken care of naturally. - Unify definition of "major faults": the definition of "major fault" is slightly changed when used in accounting (not VM_FAULT_MAJOR). More information in patch 1. - Always account the page fault onto the one that triggered the page fault. This does not matter much for #PF handlings, but mostly for gup. More information on this in patch 25. Patchset layout: Patch 1: Introduced the accounting in handle_mm_fault(), not enabled. Patch 2-23: Enable the new accounting for arch #PF handlers one by one. Patch 24: Enable the new accounting for the rest outliers (gup, iommu, etc.) Patch 25: Cleanup GUP task_struct pointer since it's not needed any more This patch (of 25): This is a preparation patch to move page fault accountings into the general code in handle_mm_fault(). This includes both the per task flt_maj/flt_min counters, and the major/minor page fault perf events. To do this, the pt_regs pointer is passed into handle_mm_fault(). PERF_COUNT_SW_PAGE_FAULTS should still be kept in per-arch page fault handlers. So far, all the pt_regs pointer that passed into handle_mm_fault() is NULL, which means this patch should have no intented functional change. Suggested-by: Linus Torvalds Signed-off-by: Peter Xu Signed-off-by: Andrew Morton Cc: Albert Ou Cc: Alexander Gordeev Cc: Andy Lutomirski Cc: Benjamin Herrenschmidt Cc: Borislav Petkov Cc: Brian Cain Cc: Catalin Marinas Cc: Christian Borntraeger Cc: Chris Zankel Cc: Dave Hansen Cc: David S. Miller Cc: Geert Uytterhoeven Cc: Gerald Schaefer Cc: Greentime Hu Cc: Guo Ren Cc: Heiko Carstens Cc: Helge Deller Cc: H. Peter Anvin Cc: Ingo Molnar Cc: Ivan Kokshaysky Cc: James E.J. Bottomley Cc: John Hubbard Cc: Jonas Bonn Cc: Ley Foon Tan Cc: "Luck, Tony" Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Simek Cc: Nick Hu Cc: Palmer Dabbelt Cc: Paul Mackerras Cc: Paul Walmsley Cc: Pekka Enberg Cc: Peter Zijlstra Cc: Richard Henderson Cc: Rich Felker Cc: Russell King Cc: Stafford Horne Cc: Stefan Kristiansson Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Vasily Gorbik Cc: Vincent Chen Cc: Vineet Gupta Cc: Will Deacon Cc: Yoshinori Sato Link: http://lkml.kernel.org/r/20200707225021.200906-1-peterx@redhat.com Link: http://lkml.kernel.org/r/20200707225021.200906-2-peterx@redhat.com Signed-off-by: Linus Torvalds

uaccess: remove segment_eq

2020-08-12T17:57:58+00:00

segment_eq is only used to implement uaccess_kernel. Just open code uaccess_kernel in the arch uaccess headers and remove one layer of indirection. Signed-off-by: Christoph Hellwig Signed-off-by: Andrew Morton Acked-by: Linus Torvalds Acked-by: Greentime Hu Acked-by: Geert Uytterhoeven Cc: Nick Hu Cc: Vincent Chen Cc: Paul Walmsley Cc: Palmer Dabbelt Link: http://lkml.kernel.org/r/20200710135706.537715-5-hch@lst.de Signed-off-by: Linus Torvalds