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2017-03-09arch, mm: convert all architectures to use 5level-fixup.hKirill A. Shutemov2-0/+2
If an architecture uses 4level-fixup.h we don't need to do anything as it includes 5level-fixup.h. If an architecture uses pgtable-nop*d.h, define __ARCH_USE_5LEVEL_HACK before inclusion of the header. It makes asm-generic code to use 5level-fixup.h. If an architecture has 4-level paging or folds levels on its own, include 5level-fixup.h directly. Signed-off-by: Kirill A. Shutemov <[email protected]> Acked-by: Michal Hocko <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-03-05uaccess: drop duplicate includes from asm/uaccess.hAl Viro1-1/+0
Signed-off-by: Al Viro <[email protected]>
2017-03-05uaccess: move VERIFY_{READ,WRITE} definitions to linux/uaccess.hAl Viro1-3/+0
Signed-off-by: Al Viro <[email protected]>
2017-03-02sched/headers: Prepare to remove the <linux/mm_types.h> dependency from ↵Ingo Molnar1-0/+2
<linux/sched.h> Update code that relied on sched.h including various MM types for them. This will allow us to remove the <linux/mm_types.h> include from <linux/sched.h>. Acked-by: Linus Torvalds <[email protected]> Cc: Mike Galbraith <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Signed-off-by: Ingo Molnar <[email protected]>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar1-0/+2
<linux/sched/debug.h> We are going to split <linux/sched/debug.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/debug.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <[email protected]> Cc: Mike Galbraith <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Signed-off-by: Ingo Molnar <[email protected]>
2017-02-27kprobes: move kprobe declarations to asm-generic/kprobes.hLuis R. Rodriguez1-1/+5
Often all is needed is these small helpers, instead of compiler.h or a full kprobes.h. This is important for asm helpers, in fact even some asm/kprobes.h make use of these helpers... instead just keep a generic asm file with helpers useful for asm code with the least amount of clutter as possible. Likewise we need now to also address what to do about this file for both when architectures have CONFIG_HAVE_KPROBES, and when they do not. Then for when architectures have CONFIG_HAVE_KPROBES but have disabled CONFIG_KPROBES. Right now most asm/kprobes.h do not have guards against CONFIG_KPROBES, this means most architecture code cannot include asm/kprobes.h safely. Correct this and add guards for architectures missing them. Additionally provide architectures that not have kprobes support with the default asm-generic solution. This lets us force asm/kprobes.h on the header include/linux/kprobes.h always, but most importantly we can now safely include just asm/kprobes.h on architecture code without bringing the full kitchen sink of header files. Two architectures already provided a guard against CONFIG_KPROBES on its kprobes.h: sh, arch. The rest of the architectures needed gaurds added. We avoid including any not-needed headers on asm/kprobes.h unless kprobes have been enabled. In a subsequent atomic change we can try now to remove compiler.h from include/linux/kprobes.h. During this sweep I've also identified a few architectures defining a common macro needed for both kprobes and ftrace, that of the definition of the breakput instruction up. Some refer to this as BREAKPOINT_INSTRUCTION. This must be kept outside of the #ifdef CONFIG_KPROBES guard. [[email protected]: fix arm64 build] Link: http://lkml.kernel.org/r/CAB=NE6X1WMByuARS4mZ1g9+W=LuVBnMDnh_5zyN0CLADaVh=Jw@mail.gmail.com [[email protected]: fixup for kprobes declarations moving] Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Luis R. Rodriguez <[email protected]> Signed-off-by: Stephen Rothwell <[email protected]> Acked-by: Masami Hiramatsu <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Masami Hiramatsu <[email protected]> Cc: Ananth N Mavinakayanahalli <[email protected]> Cc: Anil S Keshavamurthy <[email protected]> Cc: David S. Miller <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Steven Rostedt <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-25Merge tag 'for-next-dma_ops' of ↵Linus Torvalds2-17/+6
git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma Pull rdma DMA mapping updates from Doug Ledford: "Drop IB DMA mapping code and use core DMA code instead. Bart Van Assche noted that the ib DMA mapping code was significantly similar enough to the core DMA mapping code that with a few changes it was possible to remove the IB DMA mapping code entirely and switch the RDMA stack to use the core DMA mapping code. This resulted in a nice set of cleanups, but touched the entire tree and has been kept separate for that reason." * tag 'for-next-dma_ops' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma: (37 commits) IB/rxe, IB/rdmavt: Use dma_virt_ops instead of duplicating it IB/core: Remove ib_device.dma_device nvme-rdma: Switch from dma_device to dev.parent RDS: net: Switch from dma_device to dev.parent IB/srpt: Modify a debug statement IB/srp: Switch from dma_device to dev.parent IB/iser: Switch from dma_device to dev.parent IB/IPoIB: Switch from dma_device to dev.parent IB/rxe: Switch from dma_device to dev.parent IB/vmw_pvrdma: Switch from dma_device to dev.parent IB/usnic: Switch from dma_device to dev.parent IB/qib: Switch from dma_device to dev.parent IB/qedr: Switch from dma_device to dev.parent IB/ocrdma: Switch from dma_device to dev.parent IB/nes: Remove a superfluous assignment statement IB/mthca: Switch from dma_device to dev.parent IB/mlx5: Switch from dma_device to dev.parent IB/mlx4: Switch from dma_device to dev.parent IB/i40iw: Remove a superfluous assignment statement IB/hns: Switch from dma_device to dev.parent ...
2017-02-20Merge branch 'sched-core-for-linus' of ↵Linus Torvalds1-1/+0
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "The main changes in this (fairly busy) cycle were: - There was a class of scheduler bugs related to forgetting to update the rq-clock timestamp which can cause weird and hard to debug problems, so there's a new debug facility for this: which uncovered a whole lot of bugs which convinced us that we want to keep the debug facility. (Peter Zijlstra, Matt Fleming) - Various cputime related updates: eliminate cputime and use u64 nanoseconds directly, simplify and improve the arch interfaces, implement delayed accounting more widely, etc. - (Frederic Weisbecker) - Move code around for better structure plus cleanups (Ingo Molnar) - Move IO schedule accounting deeper into the scheduler plus related changes to improve the situation (Tejun Heo) - ... plus a round of sched/rt and sched/deadline fixes, plus other fixes, updats and cleanups" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (85 commits) sched/core: Remove unlikely() annotation from sched_move_task() sched/autogroup: Rename auto_group.[ch] to autogroup.[ch] sched/topology: Split out scheduler topology code from core.c into topology.c sched/core: Remove unnecessary #include headers sched/rq_clock: Consolidate the ordering of the rq_clock methods delayacct: Include <uapi/linux/taskstats.h> sched/core: Clean up comments sched/rt: Show the 'sched_rr_timeslice' SCHED_RR timeslice tuning knob in milliseconds sched/clock: Add dummy clear_sched_clock_stable() stub function sched/cputime: Remove generic asm headers sched/cputime: Remove unused nsec_to_cputime() s390, sched/cputime: Remove unused cputime definitions powerpc, sched/cputime: Remove unused cputime definitions s390, sched/cputime: Make arch_cpu_idle_time() to return nsecs ia64, sched/cputime: Remove unused cputime definitions ia64: Convert vtime to use nsec units directly ia64, sched/cputime: Move the nsecs based cputime headers to the last arch using it sched/cputime: Remove jiffies based cputime sched/cputime, vtime: Return nsecs instead of cputime_t to account sched/cputime: Complete nsec conversion of tick based accounting ...
2017-02-14math64, tile: Fix build failureSudip Mukherjee1-0/+2
The build of tilegx allmodconfig fails with: ../arch/tile/include/asm/div64.h:5:15: error: unknown type name 'u64' static inline u64 mul_u32_u32(u32 a, u32 b) ^~~ ../arch/tile/include/asm/div64.h:5:31: error: unknown type name 'u32' static inline u64 mul_u32_u32(u32 a, u32 b) ^~~ ../arch/tile/include/asm/div64.h:5:38: error: unknown type name 'u32' static inline u64 mul_u32_u32(u32 a, u32 b) ^~~ In file included from ../fs/ubifs/ubifs.h:26:0, from ../fs/ubifs/shrinker.c:42: ../include/linux/math64.h: In function 'mul_u64_u32_shr': ../arch/tile/include/asm/div64.h:9:21: error: implicit declaration of function 'mul_u32_u32' [-Werror=implicit-function-declaration] Include the linux/types.h in tiles div64.h to slve the problem. Fixes: 9e3d6223d209 ("math64, timers: Fix 32bit mul_u64_u32_shr() and friends") Signed-off-by: Sudip Mukherjee <[email protected]> Acked-by: Chris Metcalf <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Sudip Mukherjee <[email protected]> Link: http://lkml.kernel.org/r/1485275961-20112-1-git-send-email-sudip.mukherjee@codethink.co.uk Signed-off-by: Thomas Gleixner <[email protected]>
2017-02-01sched/cputime: Remove generic asm headersFrederic Weisbecker1-1/+0
cputime_t is now only used by two architectures: * powerpc (when CONFIG_VIRT_CPU_ACCOUNTING_NATIVE=y) * s390 And since the core doesn't use it anymore, we don't need any arch support from the others. So we can remove their stub implementations. A final cleanup would be to provide an efficient pure arch implementation of cputime_to_nsec() for s390 and powerpc and finally remove include/linux/cputime.h . Signed-off-by: Frederic Weisbecker <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Fenghua Yu <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Martin Schwidefsky <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Rik van Riel <[email protected]> Cc: Stanislaw Gruszka <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Tony Luck <[email protected]> Cc: Wanpeng Li <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2017-01-24treewide: Consolidate get_dma_ops() implementationsBart Van Assche1-5/+2
Introduce a new architecture-specific get_arch_dma_ops() function that takes a struct bus_type * argument. Add get_dma_ops() in <linux/dma-mapping.h>. Signed-off-by: Bart Van Assche <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Boris Ostrovsky <[email protected]> Cc: David Woodhouse <[email protected]> Cc: Juergen Gross <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: [email protected] Cc: [email protected] Cc: Russell King <[email protected]> Cc: [email protected] Signed-off-by: Doug Ledford <[email protected]>
2017-01-24treewide: Consolidate set_dma_ops() implementationsBart Van Assche1-5/+0
Now that all set_dma_ops() implementations are identical (ignoring BUG_ON() statements), remove the architecture specific definitions and add a definition in <linux/dma-mapping.h>. Signed-off-by: Bart Van Assche <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Chris Metcalf <[email protected]> Cc: David Woodhouse <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: Paul Mackerras <[email protected]> Cc: Russell King <[email protected]> Signed-off-by: Doug Ledford <[email protected]>
2017-01-24treewide: Move dma_ops from struct dev_archdata into struct deviceBart Van Assche2-6/+3
Some but not all architectures provide set_dma_ops(). Move dma_ops from struct dev_archdata into struct device such that it becomes possible on all architectures to configure dma_ops per device. Signed-off-by: Bart Van Assche <[email protected]> Acked-by: Greg Kroah-Hartman <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Boris Ostrovsky <[email protected]> Cc: David Woodhouse <[email protected]> Cc: Juergen Gross <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: [email protected] Cc: [email protected] Cc: Russell King <[email protected]> Cc: [email protected] Signed-off-by: Doug Ledford <[email protected]>
2017-01-24treewide: Constify most dma_map_ops structuresBart Van Assche2-7/+7
Most dma_map_ops structures are never modified. Constify these structures such that these can be write-protected. This patch has been generated as follows: git grep -l 'struct dma_map_ops' | xargs -d\\n sed -i \ -e 's/struct dma_map_ops/const struct dma_map_ops/g' \ -e 's/const struct dma_map_ops {/struct dma_map_ops {/g' \ -e 's/^const struct dma_map_ops;$/struct dma_map_ops;/' \ -e 's/const const struct dma_map_ops /const struct dma_map_ops /g'; sed -i -e 's/const \(struct dma_map_ops intel_dma_ops\)/\1/' \ $(git grep -l 'struct dma_map_ops intel_dma_ops'); sed -i -e 's/const \(struct dma_map_ops dma_iommu_ops\)/\1/' \ $(git grep -l 'struct dma_map_ops' | grep ^arch/powerpc); sed -i -e '/^struct vmd_dev {$/,/^};$/ s/const \(struct dma_map_ops[[:blank:]]dma_ops;\)/\1/' \ -e '/^static void vmd_setup_dma_ops/,/^}$/ s/const \(struct dma_map_ops \*dest\)/\1/' \ -e 's/const \(struct dma_map_ops \*dest = \&vmd->dma_ops\)/\1/' \ drivers/pci/host/*.c sed -i -e '/^void __init pci_iommu_alloc(void)$/,/^}$/ s/dma_ops->/intel_dma_ops./' arch/ia64/kernel/pci-dma.c sed -i -e 's/static const struct dma_map_ops sn_dma_ops/static struct dma_map_ops sn_dma_ops/' arch/ia64/sn/pci/pci_dma.c sed -i -e 's/(const struct dma_map_ops \*)//' drivers/misc/mic/bus/vop_bus.c Signed-off-by: Bart Van Assche <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Boris Ostrovsky <[email protected]> Cc: David Woodhouse <[email protected]> Cc: Juergen Gross <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: [email protected] Cc: [email protected] Cc: Russell King <[email protected]> Cc: [email protected] Signed-off-by: Doug Ledford <[email protected]>
2017-01-14math64, timers: Fix 32bit mul_u64_u32_shr() and friendsPeter Zijlstra2-1/+14
It turns out that while GCC-4.4 manages to generate 32x32->64 mult instructions for the 32bit mul_u64_u32_shr() code, any GCC after that fails horribly. Fix this by providing an explicit mul_u32_u32() function which can be architcture provided. Reported-by: Chris Metcalf <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Acked-by: Chris Metcalf <[email protected]> [for tile] Cc: Christopher S. Hall <[email protected]> Cc: David Gibson <[email protected]> Cc: John Stultz <[email protected]> Cc: Laurent Vivier <[email protected]> Cc: Liav Rehana <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Parit Bhargava <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Richard Cochran <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2016-12-17Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tileLinus Torvalds2-8/+2
Pull arch/tile updates from Chris Metcalf: "Another grab-bag of miscellaneous changes" * git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile: tile: use __ro_after_init instead of tile-specific __write_once tile: migrate exception table users off module.h and onto extable.h tile: remove #pragma unroll from finv_buffer_remote() tile-module: Rename jump labels in module_alloc() tile-module: Use kmalloc_array() in module_alloc() tile/pci_gx: fix spelling mistake: "delievered" -> "delivered"
2016-12-16tile: use __ro_after_init instead of tile-specific __write_onceChris Metcalf2-8/+2
The semantics of the old tile __write_once are the same as the newer generic __ro_after_init, so rename them all and get rid of the tile-specific version. This does not enable actual support for __ro_after_init, which had been dropped from the tile architecture before the initial upstreaming was done, since we had at that time switched to using 16MB huge pages to map the kernel. Signed-off-by: Chris Metcalf <[email protected]>
2016-11-22Merge branch 'linus' into locking/core, to pick up fixesIngo Molnar1-0/+3
Signed-off-by: Ingo Molnar <[email protected]>
2016-11-17locking/core: Provide common cpu_relax_yield() definitionChristian Borntraeger1-2/+0
No need to duplicate the same define everywhere. Since the only user is stop-machine and the only provider is s390, we can use a default implementation of cpu_relax_yield() in sched.h. Suggested-by: Russell King <[email protected]> Signed-off-by: Christian Borntraeger <[email protected]> Reviewed-by: David Hildenbrand <[email protected]> Acked-by: Russell King <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Martin Schwidefsky <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: Noam Camus <[email protected]> Cc: Paul E. McKenney <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Will Deacon <[email protected]> Cc: [email protected] Cc: [email protected] Cc: linux-s390 <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2016-11-16locking/core, arch: Remove cpu_relax_lowlatency()Christian Borntraeger1-1/+0
As there are no users left, we can remove cpu_relax_lowlatency() implementations from every architecture. Signed-off-by: Christian Borntraeger <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Martin Schwidefsky <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: Noam Camus <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Russell King <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Will Deacon <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2016-11-16locking/core: Introduce cpu_relax_yield()Christian Borntraeger1-0/+1
For spinning loops people do often use barrier() or cpu_relax(). For most architectures cpu_relax and barrier are the same, but on some architectures cpu_relax can add some latency. For example on power,sparc64 and arc, cpu_relax can shift the CPU towards other hardware threads in an SMT environment. On s390 cpu_relax does even more, it uses an hypercall to the hypervisor to give up the timeslice. In contrast to the SMT yielding this can result in larger latencies. In some places this latency is unwanted, so another variant "cpu_relax_lowlatency" was introduced. Before this is used in more and more places, lets revert the logic and provide a cpu_relax_yield that can be called in places where yielding is more important than latency. By default this is the same as cpu_relax on all architectures. Signed-off-by: Christian Borntraeger <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Martin Schwidefsky <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: Noam Camus <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Russell King <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Will Deacon <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2016-11-14tile: handle __ro_after_init like parisc doesChris Metcalf1-0/+3
The tile architecture already marks RO_DATA as read-only in the kernel, so grouping RO_AFTER_INIT_DATA with RO_DATA, as is done by default, means the kernel faults in init when it tries to write to RO_AFTER_INIT_DATA. For now, just arrange that __ro_after_init is handled like __write_once, i.e. __read_mostly. Reviewed-by: Kees Cook <[email protected]> Signed-off-by: Chris Metcalf <[email protected]>
2016-10-25locking/mutex: Kill arch specific codePeter Zijlstra1-1/+0
Its all generic atomic_long_t stuff now. Tested-by: Jason Low <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Paul E. McKenney <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Cc: [email protected] Signed-off-by: Ingo Molnar <[email protected]>
2016-10-07arch/tile: adopt the new nmi_backtrace frameworkChris Metcalf1-2/+3
Previously tile was rolling its own method of capturing backtrace data in the NMI handlers, but it was relying on running printk() from the NMI handler, which is not always safe. So adopt the nmi_backtrace model (with the new cpumask extension) instead. So we can call the nmi_backtrace code directly from the nmi handler, move the nmi_enter()/exit() into the top-level tile NMI handler. The semantics of the routine change slightly since it is now synchronous with the remote cores completing the backtraces. Previously it was asynchronous, but with protection to avoid starting a new remote backtrace if the old one was still in progress. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Chris Metcalf <[email protected]> Cc: Daniel Thompson <[email protected]> [arm] Cc: Petr Mladek <[email protected]> Cc: Aaron Tomlin <[email protected]> Cc: Peter Zijlstra (Intel) <[email protected]> Cc: "Rafael J. Wysocki" <[email protected]> Cc: Russell King <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2016-08-30mm/usercopy: get rid of CONFIG_DEBUG_STRICT_USER_COPY_CHECKSJosh Poimboeuf1-12/+10
There are three usercopy warnings which are currently being silenced for gcc 4.6 and newer: 1) "copy_from_user() buffer size is too small" compile warning/error This is a static warning which happens when object size and copy size are both const, and copy size > object size. I didn't see any false positives for this one. So the function warning attribute seems to be working fine here. Note this scenario is always a bug and so I think it should be changed to *always* be an error, regardless of CONFIG_DEBUG_STRICT_USER_COPY_CHECKS. 2) "copy_from_user() buffer size is not provably correct" compile warning This is another static warning which happens when I enable __compiletime_object_size() for new compilers (and CONFIG_DEBUG_STRICT_USER_COPY_CHECKS). It happens when object size is const, but copy size is *not*. In this case there's no way to compare the two at build time, so it gives the warning. (Note the warning is a byproduct of the fact that gcc has no way of knowing whether the overflow function will be called, so the call isn't dead code and the warning attribute is activated.) So this warning seems to only indicate "this is an unusual pattern, maybe you should check it out" rather than "this is a bug". I get 102(!) of these warnings with allyesconfig and the __compiletime_object_size() gcc check removed. I don't know if there are any real bugs hiding in there, but from looking at a small sample, I didn't see any. According to Kees, it does sometimes find real bugs. But the false positive rate seems high. 3) "Buffer overflow detected" runtime warning This is a runtime warning where object size is const, and copy size > object size. All three warnings (both static and runtime) were completely disabled for gcc 4.6 with the following commit: 2fb0815c9ee6 ("gcc4: disable __compiletime_object_size for GCC 4.6+") That commit mistakenly assumed that the false positives were caused by a gcc bug in __compiletime_object_size(). But in fact, __compiletime_object_size() seems to be working fine. The false positives were instead triggered by #2 above. (Though I don't have an explanation for why the warnings supposedly only started showing up in gcc 4.6.) So remove warning #2 to get rid of all the false positives, and re-enable warnings #1 and #3 by reverting the above commit. Furthermore, since #1 is a real bug which is detected at compile time, upgrade it to always be an error. Having done all that, CONFIG_DEBUG_STRICT_USER_COPY_CHECKS is no longer needed. Signed-off-by: Josh Poimboeuf <[email protected]> Cc: Kees Cook <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: "H . Peter Anvin" <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Steven Rostedt <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Frederic Weisbecker <[email protected]> Cc: Byungchul Park <[email protected]> Cc: Nilay Vaish <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2016-08-02signal: consolidate {TS,TLF}_RESTORE_SIGMASK codeAndy Lutomirski1-27/+0
In general, there's no need for the "restore sigmask" flag to live in ti->flags. alpha, ia64, microblaze, powerpc, sh, sparc (64-bit only), tile, and x86 use essentially identical alternative implementations, placing the flag in ti->status. Replace those optimized implementations with an equally good common implementation that stores it in a bitfield in struct task_struct and drop the custom implementations. Additional architectures can opt in by removing their TIF_RESTORE_SIGMASK defines. Link: http://lkml.kernel.org/r/8a14321d64a28e40adfddc90e18a96c086a6d6f9.1468522723.git.luto@kernel.org Signed-off-by: Andy Lutomirski <[email protected]> Tested-by: Michael Ellerman <[email protected]> [powerpc] Cc: Richard Henderson <[email protected]> Cc: Ivan Kokshaysky <[email protected]> Cc: Matt Turner <[email protected]> Cc: Tony Luck <[email protected]> Cc: Fenghua Yu <[email protected]> Cc: Michal Simek <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Yoshinori Sato <[email protected]> Cc: Rich Felker <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Chris Metcalf <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Dmitry Safonov <[email protected]> Cc: Oleg Nesterov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2016-07-27Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tileLinus Torvalds3-0/+8
Pull tile architecture updates from Chris Metcalf: "A few stray changes" * git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile: tile: Define AT_VECTOR_SIZE_ARCH for ARCH_DLINFO tile: support gcc 7 optimization to use __multi3 tile 32-bit big-endian: fix bugs in syscall argument order tile: allow disabling CONFIG_EARLY_PRINTK
2016-07-25Merge branch 'locking-core-for-linus' of ↵Linus Torvalds6-80/+150
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Ingo Molnar: "The locking tree was busier in this cycle than the usual pattern - a couple of major projects happened to coincide. The main changes are: - implement the atomic_fetch_{add,sub,and,or,xor}() API natively across all SMP architectures (Peter Zijlstra) - add atomic_fetch_{inc/dec}() as well, using the generic primitives (Davidlohr Bueso) - optimize various aspects of rwsems (Jason Low, Davidlohr Bueso, Waiman Long) - optimize smp_cond_load_acquire() on arm64 and implement LSE based atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}() on arm64 (Will Deacon) - introduce smp_acquire__after_ctrl_dep() and fix various barrier mis-uses and bugs (Peter Zijlstra) - after discovering ancient spin_unlock_wait() barrier bugs in its implementation and usage, strengthen its semantics and update/fix usage sites (Peter Zijlstra) - optimize mutex_trylock() fastpath (Peter Zijlstra) - ... misc fixes and cleanups" * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits) locking/atomic: Introduce inc/dec variants for the atomic_fetch_$op() API locking/barriers, arch/arm64: Implement LDXR+WFE based smp_cond_load_acquire() locking/static_keys: Fix non static symbol Sparse warning locking/qspinlock: Use __this_cpu_dec() instead of full-blown this_cpu_dec() locking/atomic, arch/tile: Fix tilepro build locking/atomic, arch/m68k: Remove comment locking/atomic, arch/arc: Fix build locking/Documentation: Clarify limited control-dependency scope locking/atomic, arch/rwsem: Employ atomic_long_fetch_add() locking/atomic, arch/qrwlock: Employ atomic_fetch_add_acquire() locking/atomic, arch/mips: Convert to _relaxed atomics locking/atomic, arch/alpha: Convert to _relaxed atomics locking/atomic: Remove the deprecated atomic_{set,clear}_mask() functions locking/atomic: Remove linux/atomic.h:atomic_fetch_or() locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}() locking/atomic: Fix atomic64_relaxed() bits locking/atomic, arch/xtensa: Implement atomic_fetch_{add,sub,and,or,xor}() locking/atomic, arch/x86: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() locking/atomic, arch/tile: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() locking/atomic, arch/sparc: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() ...
2016-07-25tile: Define AT_VECTOR_SIZE_ARCH for ARCH_DLINFOJames Hogan2-0/+3
AT_VECTOR_SIZE_ARCH should be defined with the maximum number of NEW_AUX_ENT entries that ARCH_DLINFO can contain, but it wasn't defined for tile at all even though ARCH_DLINFO will contain one NEW_AUX_ENT for the VDSO address. This shouldn't be a problem as AT_VECTOR_SIZE_BASE includes space for AT_BASE_PLATFORM which tile doesn't use, but lets define it now and add the comment above ARCH_DLINFO as found in several other architectures to remind future modifiers of ARCH_DLINFO to keep AT_VECTOR_SIZE_ARCH up to date. Fixes: 4a556f4f56da ("tile: implement gettimeofday() via vDSO") Signed-off-by: James Hogan <[email protected]> Cc: Chris Metcalf <[email protected]> Signed-off-by: Chris Metcalf <[email protected]>
2016-06-24Clarify naming of thread info/stack allocatorsLinus Torvalds1-1/+1
We've had the thread info allocated together with the thread stack for most architectures for a long time (since the thread_info was split off from the task struct), but that is about to change. But the patches that move the thread info to be off-stack (and a part of the task struct instead) made it clear how confused the allocator and freeing functions are. Because the common case was that we share an allocation with the thread stack and the thread_info, the two pointers were identical. That identity then meant that we would have things like ti = alloc_thread_info_node(tsk, node); ... tsk->stack = ti; which certainly _worked_ (since stack and thread_info have the same value), but is rather confusing: why are we assigning a thread_info to the stack? And if we move the thread_info away, the "confusing" code just gets to be entirely bogus. So remove all this confusion, and make it clear that we are doing the stack allocation by renaming and clarifying the function names to be about the stack. The fact that the thread_info then shares the allocation is an implementation detail, and not really about the allocation itself. This is a pure renaming and type fix: we pass in the same pointer, it's just that we clarify what the pointer means. The ia64 code that actually only has one single allocation (for all of task_struct, thread_info and kernel thread stack) now looks a bit odd, but since "tsk->stack" is actually not even used there, that oddity doesn't matter. It would be a separate thing to clean that up, I intentionally left the ia64 changes as a pure brute-force renaming and type change. Acked-by: Andy Lutomirski <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2016-06-24locking/atomic, arch/tile: Fix tilepro buildPeter Zijlstra2-19/+19
The tilepro change wasn't ever compiled it seems (the 0day built bot also doesn't have a toolchain for it). Make it work. The thing that makes the patch bigger than desired is namespace collision with the C11 __atomic builtin functions. So rename the tilepro functions to __atomic32. Reported-by: Sudip Mukherjee <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Acked-by: Chris Metcalf <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Stephen Rothwell <[email protected]> Cc: Thomas Gleixner <[email protected]> Fixes: 1af5de9af138 ("locking/atomic, arch/tile: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()") Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2016-06-16locking/atomic: Remove linux/atomic.h:atomic_fetch_or()Peter Zijlstra1-2/+0
Since all architectures have this implemented now natively, remove this dead code. Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Paul E. McKenney <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Cc: [email protected] Signed-off-by: Ingo Molnar <[email protected]>
2016-06-16locking/atomic, arch/tile: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()Peter Zijlstra4-66/+131
Implement FETCH-OP atomic primitives, these are very similar to the existing OP-RETURN primitives we already have, except they return the value of the atomic variable _before_ modification. This is especially useful for irreversible operations -- such as bitops (because it becomes impossible to reconstruct the state prior to modification). Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Acked-by: Chris Metcalf <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Paul E. McKenney <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Cc: [email protected] Signed-off-by: Ingo Molnar <[email protected]>
2016-06-14locking/barriers, tile: Provide TILE specific smp_acquire__after_ctrl_dep()Peter Zijlstra1-0/+7
Since TILE doesn't do read speculation, its control dependencies also guarantee LOAD->LOAD order and we don't need the additional RMB otherwise required to provide ACQUIRE semantics. Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Acked-by: Chris Metcalf <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Paul E. McKenney <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Signed-off-by: Ingo Molnar <[email protected]>
2016-06-07tile: allow disabling CONFIG_EARLY_PRINTKChris Metcalf1-0/+5
In that case, any users of early_panic() end up calling panic(). Signed-off-by: Chris Metcalf <[email protected]>
2016-05-24Merge tag 'asm-generic-4.7' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic cleanup from Arnd Bergmann: "I have only one patch for asm-generic in this release, this one is from James Hogan and updates the generic system call table for renameat2 so we don't need to provide both renameat and renameat2 in newly added architectures" * tag 'asm-generic-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: asm-generic: Drop renameat syscall from default list
2016-05-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tileLinus Torvalds1-2/+15
Pull arch/tile updates from Chris Metcalf: "This is an even quieter cycle than usual" * git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile: Fix typo Fix typo Fix typo tile: sort the "select" lines in the TILE/TILEGX configs tile: clarify barrier semantics of atomic_add_return tile/defconfigs: Remove CONFIG_IPV6_PRIVACY
2016-05-19arch: fix has_transparent_hugepage()Hugh Dickins1-1/+0
I've just discovered that the useful-sounding has_transparent_hugepage() is actually an architecture-dependent minefield: on some arches it only builds if CONFIG_TRANSPARENT_HUGEPAGE=y, on others it's also there when not, but on some of those (arm and arm64) it then gives the wrong answer; and on mips alone it's marked __init, which would crash if called later (but so far it has not been called later). Straighten this out: make it available to all configs, with a sensible default in asm-generic/pgtable.h, removing its definitions from those arches (arc, arm, arm64, sparc, tile) which are served by the default, adding #define has_transparent_hugepage has_transparent_hugepage to those (mips, powerpc, s390, x86) which need to override the default at runtime, and removing the __init from mips (but maybe that kind of code should be avoided after init: set a static variable the first time it's called). Signed-off-by: Hugh Dickins <[email protected]> Cc: "Kirill A. Shutemov" <[email protected]> Cc: Andrea Arcangeli <[email protected]> Cc: Andres Lagar-Cavilla <[email protected]> Cc: Yang Shi <[email protected]> Cc: Ning Qu <[email protected]> Cc: Mel Gorman <[email protected]> Cc: Konstantin Khlebnikov <[email protected]> Acked-by: David S. Miller <[email protected]> Acked-by: Vineet Gupta <[email protected]> [arch/arc] Acked-by: Gerald Schaefer <[email protected]> [arch/s390] Acked-by: Ingo Molnar <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2016-05-05asm-generic: Drop renameat syscall from default listJames Hogan1-0/+1
The newer renameat2 syscall provides all the functionality provided by the renameat syscall and adds flags, so future architectures won't need to include renameat. Therefore drop the renameat syscall from the generic syscall list unless __ARCH_WANT_RENAMEAT is defined by the architecture's unistd.h prior to including asm-generic/unistd.h, and adjust all architectures using the generic syscall list to define it so that no in-tree architectures are affected. Signed-off-by: James Hogan <[email protected]> Acked-by: Vineet Gupta <[email protected]> Cc: [email protected] Cc: [email protected] Cc: Catalin Marinas <[email protected]> Cc: Will Deacon <[email protected]> Cc: [email protected] Cc: Mark Salter <[email protected]> Cc: Aurelien Jacquiot <[email protected]> Cc: [email protected] Cc: Richard Kuo <[email protected]> Cc: [email protected] Cc: [email protected] Cc: Jonas Bonn <[email protected]> Cc: [email protected] Cc: Chen Liqin <[email protected]> Cc: Lennox Wu <[email protected]> Cc: Chris Metcalf <[email protected]> Cc: Guan Xuetao <[email protected]> Cc: Ley Foon Tan <[email protected]> Cc: [email protected] Cc: Yoshinori Sato <[email protected]> Cc: [email protected] Signed-off-by: Arnd Bergmann <[email protected]>
2016-04-26tile: clarify barrier semantics of atomic_add_returnChris Metcalf1-2/+15
A recent discussion on LKML made it clear that the one-line comment previously in atomic_add_return() was not clear enough: https://lkml.kernel.org/r/[email protected] Signed-off-by: Chris Metcalf <[email protected]>
2016-03-28Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tileLinus Torvalds1-13/+13
Pull arch/tile bugfixes from Chris Metcalf: "These include updates to MAINTAINERS, some comment spelling fixes, and a bugfix to the tile kgdb.c support" * git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile: tile: Fix misspellings in comments. MAINTAINERS: update web link for tile architecture MAINTAINERS: update arch/tile maintainer email domain tile kgdb: fix bug in copy to gdb regs, and optimize memset
2016-03-07PCI: Move pci_dma_* helpers to common codeChristoph Hellwig1-3/+0
For a long time all architectures implement the pci_dma_* functions using the generic DMA API, and they all use the same header to do so. Move this header, pci-dma-compat.h, to include/linux and include it from the generic pci.h instead of having each arch duplicate this include. Signed-off-by: Christoph Hellwig <[email protected]> Signed-off-by: Bjorn Helgaas <[email protected]>
2016-03-04tile: Fix misspellings in comments.Adam Buchbinder1-13/+13
Signed-off-by: Adam Buchbinder <[email protected]> Signed-off-by: Chris Metcalf <[email protected]> [plus "uninitalization"]
2016-01-20dma-mapping: always provide the dma_map_ops based implementationChristoph Hellwig1-3/+0
Move the generic implementation to <linux/dma-mapping.h> now that all architectures support it and remove the HAVE_DMA_ATTR Kconfig symbol now that everyone supports them. [[email protected]: remove leftovers in Kconfig] Signed-off-by: Christoph Hellwig <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Aurelien Jacquiot <[email protected]> Cc: Chris Metcalf <[email protected]> Cc: David Howells <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Cc: Haavard Skinnemoen <[email protected]> Cc: Hans-Christian Egtvedt <[email protected]> Cc: Helge Deller <[email protected]> Cc: James Hogan <[email protected]> Cc: Jesper Nilsson <[email protected]> Cc: Koichi Yasutake <[email protected]> Cc: Ley Foon Tan <[email protected]> Cc: Mark Salter <[email protected]> Cc: Mikael Starvik <[email protected]> Cc: Steven Miao <[email protected]> Cc: Vineet Gupta <[email protected]> Cc: Christian Borntraeger <[email protected]> Cc: Joerg Roedel <[email protected]> Cc: Sebastian Ott <[email protected]> Signed-off-by: Valentin Rothberg <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2016-01-20tile: uninline dma_set_maskChristoph Hellwig1-28/+1
We'll soon merge <asm-generic/dma-mapping-common.h> into <linux/dma-mapping.h> and the reference to dma_capable in the tile dma_set_mask would create a circular dependency. Fix this by moving the implementation out of line. Signed-off-by: Christoph Hellwig <[email protected]> Cc: Chris Metcalf <[email protected]> Cc: Christian Borntraeger <[email protected]> Cc: Joerg Roedel <[email protected]> Cc: Sebastian Ott <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2016-01-18Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds1-4/+5
Pull virtio barrier rework+fixes from Michael Tsirkin: "This adds a new kind of barrier, and reworks virtio and xen to use it. Plus some fixes here and there" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (44 commits) checkpatch: add virt barriers checkpatch: check for __smp outside barrier.h checkpatch.pl: add missing memory barriers virtio: make find_vqs() checkpatch.pl-friendly virtio_balloon: fix race between migration and ballooning virtio_balloon: fix race by fill and leak s390: more efficient smp barriers s390: use generic memory barriers xen/events: use virt_xxx barriers xen/io: use virt_xxx barriers xenbus: use virt_xxx barriers virtio_ring: use virt_store_mb sh: move xchg_cmpxchg to a header by itself sh: support 1 and 2 byte xchg virtio_ring: update weak barriers to use virt_xxx Revert "virtio_ring: Update weak barriers to use dma_wmb/rmb" asm-generic: implement virt_xxx memory barriers x86: define __smp_xxx xtensa: define __smp_xxx tile: define __smp_xxx ...
2016-01-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tileLinus Torvalds7-14/+142
Pull arch/tile updates from Chris Metcalf: "This is a grab bag of changes that includes some NOHZ and context-tracking related changes, some debugging improvements, JUMP_LABEL support, and some fixes for tilepro allmodconfig support. We also remove the now-unused node_has_online_mem() definitions both for tile's asm/topology.h as well as in linux/topology.h itself" * git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile: numa: remove stale node_has_online_mem() define arch/tile: move user_exit() to early kernel entry sequence tile: fix bug in setting PT_FLAGS_DISABLE_IRQ on kernel entry tile: fix tilepro casts for readl, writel, etc tile: fix a -Wframe-larger-than warning tile: include the syscall number in the backtrace MAINTAINERS: add git URL for tile arch/tile: adopt prepare_exit_to_usermode() model from x86 tile/jump_label: add jump label support for TILE-Gx tile: define a macro ktext_writable_addr to get writable kernel text address
2016-01-18numa: remove stale node_has_online_mem() defineChris Metcalf1-3/+0
This isn't used anywhere, so delete it. Looks like the last usage (in x86-specific code) was removed by Tejun in 2011 in commit bd6709a91a59 ("x86, NUMA: Make 32bit use common NUMA init path"). Signed-off-by: Chris Metcalf <[email protected]>
2016-01-18tile: fix tilepro casts for readl, writel, etcChris Metcalf1-8/+8
Missing parentheses could cause an argument of the form "integer + pointer" to get cast to "(long)integer + pointer" and remain a pointer type, causing compiler warnings. Signed-off-by: Chris Metcalf <[email protected]>
2016-01-18arch/tile: adopt prepare_exit_to_usermode() model from x86Chris Metcalf2-3/+7
This change is a prerequisite change for TASK_ISOLATION but also stands on its own for readability and maintainability. The existing tile do_work_pending() was called in a loop from assembly on the slow path; this change moves the loop into C code as well. For the x86 version see commit c5c46f59e4e7 ("x86/entry: Add new, comprehensible entry and exit handlers written in C"). This change exposes a pre-existing bug on the older tilepro platform; the singlestep processing is done last, but on tilepro (unlike tilegx) we enable interrupts while doing that processing, so we could in theory miss a signal or other asynchronous event. A future change could fix this by breaking the singlestep work into a "prepare" step done in the main loop, and a "trigger" step done after exiting the loop. Since this change is intended as purely a restructuring change, we call out the bug explicitly now, but don't yet fix it. Signed-off-by: Chris Metcalf <[email protected]>