- 26 Mar, 2017 9 commits
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Peter Zijlstra authored
commit e7cc4865 upstream. While hunting for clues to a use-after-free, Oleg spotted that perf_event_init_context() can loose an error value with the result that fork() can succeed even though we did not fully inherit the perf event context. Spotted-by:
Oleg Nesterov <oleg@redhat.com> Signed-off-by:
Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: oleg@redhat.com Fixes: 889ff015 ("perf/core: Split context's event group list into pinned and non-pinned lists") Link: http://lkml.kernel.org/r/20170316125823.190342547@infradead.orgSigned-off-by:
Ingo Molnar <mingo@kernel.org> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Peter Zijlstra authored
commit e552a838 upstream. Dmitry reported syzcaller tripped a use-after-free in perf_release(). After much puzzlement Oleg spotted the below scenario: Task1 Task2 fork() perf_event_init_task() /* ... */ goto bad_fork_$foo; /* ... */ perf_event_free_task() mutex_lock(ctx->lock) perf_free_event(B) perf_event_release_kernel(A) mutex_lock(A->child_mutex) list_for_each_entry(child, ...) { /* child == B */ ctx = B->ctx; get_ctx(ctx); mutex_unlock(A->child_mutex); mutex_lock(A->child_mutex) list_del_init(B->child_list) mutex_unlock(A->child_mutex) /* ... */ mutex_unlock(ctx->lock); put_ctx() /* >0 */ free_task(); mutex_lock(ctx->lock); mutex_lock(A->child_mutex); /* ... */ mutex_unlock(A->child_mutex); mutex_unlock(ctx->lock) put_ctx() /* 0 */ ctx->task && !TOMBSTONE put_task_struct() /* UAF */ This patch closes the hole by making perf_event_free_task() destroy the task <-> ctx relation such that perf_event_release_kernel() will no longer observe the now dead task. Spotted-by:
Dmitry Vyukov <dvyukov@google.com> Signed-off-by:
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Helge Deller authored
commit 73580dac upstream. On those parisc machines which don't provide a software power off function, the system currently kills the init process at the end of a shutdown and unexpectedly restarts insteads of halting. Fix it by adding a loop which will not return. Signed-off-by:
Helge Deller <deller@gmx.de> Signed-off-by:
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John David Anglin authored
commit 316ec062 upstream. The previously submitted patch did not resolve the random segmentation faults observed on the phantom buildd system. There are still unresolved problems with the Debian 4.8 and 4.9 kernels on C8000. The attached patch removes the flush of the offset map pages and does a whole data cache flush for large ranges. No other arch flushes the offset map in these routines as far as I can tell. I have not observed any random segmentation faults on rp3440 in two weeks of testing with 4.10.0 and 4.10.1. Signed-off-by:
John David Anglin <dave.anglin@bell.net> Signed-off-by:
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Quinn Tran authored
commit 8b666809 upstream. When FW notify driver or driver detects low FW resource, driver tries to send out Busy SCSI Status to tell Initiator side to back off. During the send process, the lock was not held. Signed-off-by:
Quinn Tran <quinn.tran@qlogic.com> Signed-off-by:
Himanshu Madhani <himanshu.madhani@cavium.com> Signed-off-by:
Nicholas Bellinger <nab@linux-iscsi.org> Signed-off-by:
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Quinn Tran authored
commit ae940f2c upstream. Signed-off-by:
Quinn Tran <quinn.tran@cavium.com> Signed-off-by:
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Linus Torvalds authored
commit 474c9015 upstream. gcc-7 has an "optimization" pass that completely screws up, and generates the code expansion for the (impossible) case of calling ilog2() with a zero constant, even when the code gcc compiles does not actually have a zero constant. And we try to generate a compile-time error for anybody doing ilog2() on a constant where that doesn't make sense (be it zero or negative). So now gcc7 will fail the build due to our sanity checking, because it created that constant-zero case that didn't actually exist in the source code. There's a whole long discussion on the kernel mailing about how to work around this gcc bug. The gcc people themselevs have discussed their "feature" in https://gcc.gnu.org/bugzilla/show_bug.cgi?id=72785 but it's all water under the bridge, because while it looked at one point like it would be solved by the time gcc7 was released, that was not to be. So now we have to deal with this compiler braindamage. And the only simple approach seems to be to just delete the code that tries to warn about bad uses of ilog2(). So now "ilog2()" will just return 0 not just for the value 1, but for any non-positive value too. It's not like I can recall anybody having ever actually tried to use this function on any invalid value, but maybe the sanity check just meant that such code never made it out in public. Reported-by:
Laura Abbott <labbott@redhat.com> Cc: John Stultz <john.stultz@linaro.org>, Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> Cc: Jiri Slaby <jslaby@suse.cz> Signed-off-by:
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Eric Anholt authored
commit 3a622346 upstream. The pm_runtime_put() we were using immediately released power on the device, which meant that we were generally turning the device off and on once per frame. In many profiles I've looked at, that added up to about 1% of CPU time, but this could get worse in the case of frequent rendering and readback (as may happen in X rendering). By keeping the device on until we've been idle for a couple of frames, we drop the overhead of runtime PM down to sub-.1%. Signed-off-by:
Eric Anholt <eric@anholt.net> Cc: Amit Pundir <amit.pundir@linaro.org> Signed-off-by:
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Eric Anholt authored
commit 457e67a7 upstream. The loop is scanning until the original max_ip (size of the BO), but we want to not examine any code after the PROG_END's delay slots. There was a block trying to do that, except that we had some early continue statements if the signal wasn't a PROG_END or a BRANCH. The failure mode would be that a valid shader is rejected because some undefined memory after the PROG_END slots is parsed as a branch and the rest of its setup is illegal. I haven't seen this in the wild, but valgrind was complaining when about this up in the userland simulator mode. Signed-off-by:
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- 22 Mar, 2017 31 commits
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Greg Kroah-Hartman authored
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Daniel Axtens authored
commit aa2be9b3 upstream. Turning on crypto self-tests on a POWER8 shows: alg: hash: Test 1 failed for crc32c-vpmsum 00000000: ff ff ff ff Comparing the code with the Intel CRC32c implementation on which ours is based shows that we are doing an init with 0, not ~0 as CRC32c requires. This probably wasn't caught because btrfs does its own weird open-coded initialisation. Initialise our internal context to ~0 on init. This makes the self-tests pass, and btrfs continues to work. Fixes: 6dd7a82c ("crypto: powerpc - Add POWER8 optimised crc32c") Cc: Anton Blanchard <anton@samba.org> Signed-off-by:
Daniel Axtens <dja@axtens.net> Acked-by:
Anton Blanchard <anton@samba.org> Signed-off-by:
Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by:
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Niklas Cassel authored
commit 17fcbd59 upstream. We hang if SIGKILL has been sent, but the task is stuck in down_read() (after do_exit()), even though no task is doing down_write() on the rwsem in question: INFO: task libupnp:21868 blocked for more than 120 seconds. libupnp D 0 21868 1 0x08100008 ... Call Trace: __schedule() schedule() __down_read() do_exit() do_group_exit() __wake_up_parent() This bug has already been fixed for CONFIG_RWSEM_XCHGADD_ALGORITHM=y in the following commit: 04cafed7 ("locking/rwsem: Fix down_write_killable()") ... however, this bug also exists for CONFIG_RWSEM_GENERIC_SPINLOCK=y. Signed-off-by:
Niklas Cassel <niklas.cassel@axis.com> Signed-off-by:
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Peter Zijlstra authored
commit 9bbb25af upstream. Thomas spotted that fixup_pi_state_owner() can return errors and we fail to unlock the rt_mutex in that case. Reported-by:
Thomas Gleixner <tglx@linutronix.de> Signed-off-by:
Darren Hart <dvhart@linux.intel.com> Cc: juri.lelli@arm.com Cc: bigeasy@linutronix.de Cc: xlpang@redhat.com Cc: rostedt@goodmis.org Cc: mathieu.desnoyers@efficios.com Cc: jdesfossez@efficios.com Cc: dvhart@infradead.org Cc: bristot@redhat.com Link: http://lkml.kernel.org/r/20170304093558.867401760@infradead.orgSigned-off-by:
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Peter Zijlstra authored
commit c236c8e9 upstream. While working on the futex code, I stumbled over this potential use-after-free scenario. Dmitry triggered it later with syzkaller. pi_mutex is a pointer into pi_state, which we drop the reference on in unqueue_me_pi(). So any access to that pointer after that is bad. Since other sites already do rt_mutex_unlock() with hb->lock held, see for example futex_lock_pi(), simply move the unlock before unqueue_me_pi(). Reported-by:
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Andy Lutomirski authored
commit 5dc855d4 upstream. If one thread mmaps a perf event while another thread in the same mm is in some context where active_mm != mm (which can happen in the scheduler, for example), refresh_pce() would write the wrong value to CR4.PCE. This broke some PAPI tests. Reported-and-tested-by:
Vince Weaver <vincent.weaver@maine.edu> Signed-off-by:
Andy Lutomirski <luto@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bpetkov@suse.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 7911d3f7 ("perf/x86: Only allow rdpmc if a perf_event is mapped") Link: http://lkml.kernel.org/r/0c5b38a76ea50e405f9abe07a13dfaef87c173a1.1489694270.git.luto@kernel.orgSigned-off-by:
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Andrey Ryabinin authored
commit be3606ff upstream. The kernel doesn't boot with both PROFILE_ANNOTATED_BRANCHES=y and KASAN=y options selected. With branch profiling enabled we end up calling ftrace_likely_update() before kasan_early_init(). ftrace_likely_update() is built with KASAN instrumentation, so calling it before kasan has been initialized leads to crash. Use DISABLE_BRANCH_PROFILING define to make sure that we don't call ftrace_likely_update() from early code before kasan_early_init(). Fixes: ef7f0d6a ("x86_64: add KASan support") Reported-by:
Fengguang Wu <fengguang.wu@intel.com> Signed-off-by:
Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: kasan-dev@googlegroups.com Cc: Alexander Potapenko <glider@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: lkp@01.org Cc: Dmitry Vyukov <dvyukov@google.com> Link: http://lkml.kernel.org/r/20170313163337.1704-1-aryabinin@virtuozzo.comSigned-off-by:
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Peter Zijlstra authored
commit 44fee88c upstream. Subhransu reported that convert_art_to_tsc() isn't working for him. The ART to TSC relation is only set up for systems which use the refined TSC calibration. Systems with known TSC frequency (available via CPUID 15) are not using the refined calibration and therefor the ART to TSC relation is never established. Add the setup to the known frequency init path which skips ART calibration. The init code needs to be duplicated as for systems which use refined calibration the ART setup must be delayed until calibration has been done. The problem has been there since the ART support was introdduced, but only detected now because Subhransu tested the first time on hardware which has TSC frequency enumerated via CPUID 15. Note for stable: The conditional has changed from TSC_RELIABLE to TSC_KNOWN_FREQUENCY. [ tglx: Rewrote changelog and identified the proper 'Fixes' commit ] Fixes: f9677e0f ("x86/tsc: Always Running Timer (ART) correlated clocksource") Reported-by:
"Prusty, Subhransu S" <subhransu.s.prusty@intel.com> Signed-off-by:
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Shanker Donthineni authored
commit 90922a2d upstream. On Qualcomm Datacenter Technologies QDF2400 SoCs, the ITS hardware implementation uses 16Bytes for Interrupt Translation Entry (ITE), but reports an incorrect value of 8Bytes in GITS_TYPER.ITTE_size. It might cause kernel memory corruption depending on the number of MSI(x) that are configured and the amount of memory that has been allocated for ITEs in its_create_device(). This patch fixes the potential memory corruption by setting the correct ITE size to 16Bytes. Cc: stable@vger.kernel.org Signed-off-by:
Shanker Donthineni <shankerd@codeaurora.org> Signed-off-by:
Marc Zyngier <marc.zyngier@arm.com> Signed-off-by:
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Marc Zyngier authored
commit 68925176 upstream. When invalidating guest TLBs, special care must be taken to actually shoot the guest TLBs and not the host ones if we're running on a VHE system. This is controlled by the HCR_EL2.TGE bit, which we forget to clear before invalidating TLBs. Address the issue by introducing two wrappers (__tlb_switch_to_guest and __tlb_switch_to_host) that take care of both the VTTBR_EL2 and HCR_EL2.TGE switching. Reported-by:
Tomasz Nowicki <tnowicki@caviumnetworks.com> Tested-by:
Christoffer Dall <cdall@linaro.org> Signed-off-by:
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Boris Brezillon authored
commit ab8df60e upstream. PV_CONTROL_CLK_SELECT_VEC is actually 2 and not 0. Fix the definition and rework the vc4_set_crtc_possible_masks() to cover the full range of the PV_CONTROL_CLK_SELECT field. Signed-off-by:
Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by:
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Derek Foreman authored
commit 26fc78f6 upstream. There was a small window where a userspace program could submit a pageflip after receiving a pageflip completion event yet still receive EBUSY. Signed-off-by:
Derek Foreman <derekf@osg.samsung.com> Signed-off-by:
Daniel Stone <daniels@collabora.com> Cc: Amit Pundir <amit.pundir@linaro.org> Signed-off-by:
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Boris Brezillon authored
commit f2a46926 upstream. There is no fixed divider on pllh_aux. Signed-off-by:
Stephen Boyd <sboyd@codeaurora.org> Cc: Amit Pundir <amit.pundir@linaro.org> Signed-off-by:
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Michael Ellerman authored
[ Upstream commit a05ef161 ] Currently the build breaks if CMA=n and SPAPR_TCE_IOMMU=y: arch/powerpc/mm/mmu_context_iommu.c: In function ‘mm_iommu_get’: arch/powerpc/mm/mmu_context_iommu.c:193:42: error: ‘MIGRATE_CMA’ undeclared (first use in this function) if (get_pageblock_migratetype(page) == MIGRATE_CMA) { ^~~~~~~~~~~ Fix it by using the existing is_migrate_cma_page(), which evaulates to false when CMA=n. Fixes: 2e5bbb54 ("KVM: PPC: Book3S HV: Migrate pinned pages out of CMA") Signed-off-by:
Michael Ellerman <mpe@ellerman.id.au> Signed-off-by:
Sasha Levin <alexander.levin@verizon.com> Signed-off-by:
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Alexandre Belloni authored
[ Upstream commit 32856eea ] Commit bbe097f0 ("usb: gadget: udc: atmel: fix endpoint name") introduced a memory leak when unbinding the driver. The endpoint names would not be freed. Solve that by including the name as a string in struct usba_ep so it is freed when the endpoint is. Signed-off-by:
Alexandre Belloni <alexandre.belloni@free-electrons.com> Signed-off-by:
Felipe Balbi <felipe.balbi@linux.intel.com> Signed-off-by:
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Gabriel Krisman Bertazi authored
[ Upstream commit f209fa03 ] During a PCI error recovery, like the ones provoked by EEH in the ppc64 platform, all IO to the device must be blocked while the recovery is completed. Current 8250_pci implementation only suspends the port instead of detaching it, which doesn't prevent incoming accesses like TIOCMGET and TIOCMSET calls from reaching the device. Those end up racing with the EEH recovery, crashing it. Similar races were also observed when opening the device and when shutting it down during recovery. This patch implements a more robust IO blockage for the 8250_pci recovery by unregistering the port at the beginning of the procedure and re-adding it afterwards. Since the port is detached from the uart layer, we can be sure that no request will make through to the device during recovery. This is similar to the solution used by the JSM serial driver. I thank Peter Hurley <peter@hurleysoftware.com> for valuable input on this one over one year ago. Signed-off-by:
Gabriel Krisman Bertazi <krisman@linux.vnet.ibm.com> Signed-off-by:
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Michael Pobega authored
[ Upstream commit 708f5dcc ] The Dell Latitude 3350's ethernet card attempts to use a reserved IRQ (18), resulting in ACPI being unable to enable the ethernet. Adding it to acpi_rev_dmi_table[] helps to work around this problem. Signed-off-by:
Michael Pobega <mpobega@neverware.com> [ rjw: Changelog ] Signed-off-by:
Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by:
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Alex Hung authored
[ Upstream commit 9523b9bf ] Precision 5520 and 3520 either hang at login and during suspend or reboot. It turns out that that adding them to acpi_rev_dmi_table[] helps to work around those issues. Signed-off-by:
Alex Hung <alex.hung@canonical.com> [ rjw: Changelog ] Signed-off-by:
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Vladimir Davydov authored
[ Upstream commit 89e364db ] synchronize_sched() is a heavy operation and calling it per each cache owned by a memory cgroup being destroyed may take quite some time. What is worse, it's currently called under the slab_mutex, stalling all works doing cache creation/destruction. Actually, there isn't much point in calling synchronize_sched() for each cache - it's enough to call it just once - after setting cpu_partial for all caches and before shrinking them. This way, we can also move it out of the slab_mutex, which we have to hold for iterating over the slab cache list. Link: https://bugzilla.kernel.org/show_bug.cgi?id=172991 Link: http://lkml.kernel.org/r/0a10d71ecae3db00fb4421bcd3f82bcc911f4be4.1475329751.git.vdavydov.dev@gmail.comSigned-off-by:
Vladimir Davydov <vdavydov.dev@gmail.com> Reported-by:
Doug Smythies <dsmythies@telus.net> Acked-by:
Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Pekka Enberg <penberg@kernel.org> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
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Henrik Ingo authored
[ Upstream commit e950267a ] Some devices have invalid baSourceID references, causing uvc_scan_chain() to fail, but if we just take the entities we can find and put them together in the most sensible chain we can think of, turns out they do work anyway. Note: This heuristic assumes there is a single chain. At the time of writing, devices known to have such a broken chain are - Acer Integrated Camera (5986:055a) - Realtek rtl157a7 (0bda:57a7) Signed-off-by:
Henrik Ingo <henrik.ingo@avoinelama.fi> Signed-off-by:
Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by:
Mauro Carvalho Chehab <mchehab@s-opensource.com> Signed-off-by:
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Harald Freudenberger authored
[ Upstream commit b3e8652b ] Signed-off-by:
Harald Freudenberger <freude@linux.vnet.ibm.com> Signed-off-by:
Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by:
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Mauricio Faria de Oliveira authored
[ Upstream commit 25cdb645 ] The WRITE_SAME commands are not present in the blk_default_cmd_filter write_ok list, and thus are failed with -EPERM when the SG_IO ioctl() is executed without CAP_SYS_RAWIO capability (e.g., unprivileged users). [ sg_io() -> blk_fill_sghdr_rq() > blk_verify_command() -> -EPERM ] The problem can be reproduced with the sg_write_same command # sg_write_same --num 1 --xferlen 512 /dev/sda # # capsh --drop=cap_sys_rawio -- -c \ 'sg_write_same --num 1 --xferlen 512 /dev/sda' Write same: pass through os error: Operation not permitted # For comparison, the WRITE_VERIFY command does not observe this problem, since it is in that list: # capsh --drop=cap_sys_rawio -- -c \ 'sg_write_verify --num 1 --ilen 512 --lba 0 /dev/sda' # So, this patch adds the WRITE_SAME commands to the list, in order for the SG_IO ioctl to finish successfully: # capsh --drop=cap_sys_rawio -- -c \ 'sg_write_same --num 1 --xferlen 512 /dev/sda' # That case happens to be exercised by QEMU KVM guests with 'scsi-block' devices (qemu "-device scsi-block" [1], libvirt "<disk type='block' device='lun'>" [2]), which employs the SG_IO ioctl() and runs as an unprivileged user (libvirt-qemu). In that scenario, when a filesystem (e.g., ext4) performs its zero-out calls, which are translated to write-same calls in the guest kernel, and then into SG_IO ioctls to the host kernel, SCSI I/O errors may be observed in the guest: [...] sd 0:0:0:0: [sda] tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE [...] sd 0:0:0:0: [sda] tag#0 Sense Key : Aborted Command [current] [...] sd 0:0:0:0: [sda] tag#0 Add. Sense: I/O process terminated [...] sd 0:0:0:0: [sda] tag#0 CDB: Write Same(10) 41 00 01 04 e0 78 00 00 08 00 [...] blk_update_request: I/O error, dev sda, sector 17096824 Links: [1] http://git.qemu.org/?p=qemu.git;a=commit;h=336a6915bc7089fb20fea4ba99972ad9a97c5f52 [2] https://libvirt.org/formatdomain.html#elementsDisks (see 'disk' -> 'device') Signed-off-by:
Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com> Signed-off-by:
Brahadambal Srinivasan <latha@linux.vnet.ibm.com> Reported-by:
Manjunatha H R <manjuhr1@in.ibm.com> Reviewed-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Jens Axboe <axboe@fb.com> Signed-off-by:
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Ben Skeggs authored
[ Upstream commit 2a32b9b1 ] Signed-off-by:
Ben Skeggs <bskeggs@redhat.com> Signed-off-by:
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Ben Skeggs authored
[ Upstream commit 4391d7f5 ] GP102/GP104 make life difficult by redefining the channel indices for some registers, but not others. Signed-off-by:
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Ben Skeggs authored
[ Upstream commit e50fcff1 ] Signed-off-by:
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Alexey Kardashevskiy authored
[ Upstream commit d9c72894 ] We are going to allow the userspace to configure container in one memory context and pass container fd to another so we are postponing memory allocations accounted against the locked memory limit. One of previous patches took care of it_userspace. At the moment we create the default DMA window when the first group is attached to a container; this is done for the userspace which is not DDW-aware but familiar with the SPAPR TCE IOMMU v2 in the part of memory pre-registration - such client expects the default DMA window to exist. This postpones the default DMA window allocation till one of the folliwing happens: 1. first map/unmap request arrives; 2. new window is requested; This adds noop for the case when the userspace requested removal of the default window which has not been created yet. Signed-off-by:
Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by:
David Gibson <david@gibson.dropbear.id.au> Acked-by:
Alex Williamson <alex.williamson@redhat.com> Signed-off-by:
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Alexey Kardashevskiy authored
[ Upstream commit 6f01cc69 ] There is already a helper to create a DMA window which does allocate a table and programs it to the IOMMU group. However tce_iommu_take_ownership_ddw() did not use it and did these 2 calls itself to simplify error path. Since we are going to delay the default window creation till the default window is accessed/removed or new window is added, we need a helper to create a default window from all these cases. This adds tce_iommu_create_default_window(). Since it relies on a VFIO container to have at least one IOMMU group (for future use), this changes tce_iommu_attach_group() to add a group to the container first and then call the new helper. Signed-off-by:
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Alexey Kardashevskiy authored
[ Upstream commit 4b6fad70 ] At the moment the userspace tool is expected to request pinning of the entire guest RAM when VFIO IOMMU SPAPR v2 driver is present. When the userspace process finishes, all the pinned pages need to be put; this is done as a part of the userspace memory context (MM) destruction which happens on the very last mmdrop(). This approach has a problem that a MM of the userspace process may live longer than the userspace process itself as kernel threads use userspace process MMs which was runnning on a CPU where the kernel thread was scheduled to. If this happened, the MM remains referenced until this exact kernel thread wakes up again and releases the very last reference to the MM, on an idle system this can take even hours. This moves preregistered regions tracking from MM to VFIO; insteads of using mm_iommu_table_group_mem_t::used, tce_container::prereg_list is added so each container releases regions which it has pre-registered. This changes the userspace interface to return EBUSY if a memory region is already registered in a container. However it should not have any practical effect as the only userspace tool available now does register memory region once per container anyway. As tce_iommu_register_pages/tce_iommu_unregister_pages are called under container->lock, this does not need additional locking. Signed-off-by:
Nicholas Piggin <npiggin@gmail.com> Acked-by:
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Alexey Kardashevskiy authored
[ Upstream commit bc82d122 ] In some situations the userspace memory context may live longer than the userspace process itself so if we need to do proper memory context cleanup, we better have tce_container take a reference to mm_struct and use it later when the process is gone (@current or @current->mm is NULL). This references mm and stores the pointer in the container; this is done in a new helper - tce_iommu_mm_set() - when one of the following happens: - a container is enabled (IOMMU v1); - a first attempt to pre-register memory is made (IOMMU v2); - a DMA window is created (IOMMU v2). The @mm stays referenced till the container is destroyed. This replaces current->mm with container->mm everywhere except debug prints. This adds a check that current->mm is the same as the one stored in the container to prevent userspace from making changes to a memory context of other processes. DMA map/unmap ioctls() do not check for @mm as they already check for @enabled which is set after tce_iommu_mm_set() is called. This does not reference a task as multiple threads within the same mm are allowed to ioctl() to vfio and supposedly they will have same limits and capabilities and if they do not, we'll just fail with no harm made. Signed-off-by:
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Alexey Kardashevskiy authored
[ Upstream commit d7baee69 ] This changes mm_iommu_xxx helpers to take mm_struct as a parameter instead of getting it from @current which in some situations may not have a valid reference to mm. This changes helpers to receive @mm and moves all references to @current to the caller, including checks for !current and !current->mm; checks in mm_iommu_preregistered() are removed as there is no caller yet. This moves the mm_iommu_adjust_locked_vm() call to the caller as it receives mm_iommu_table_group_mem_t but it needs mm. This should cause no behavioral change. Signed-off-by:
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Alexey Kardashevskiy authored
[ Upstream commit 88f54a35 ] We are going to get rid of @current references in mmu_context_boos3s64.c and cache mm_struct in the VFIO container. Since mm_context_t does not have reference counting, we will be using mm_struct which does have the reference counter. This changes mm_iommu_init/mm_iommu_cleanup to receive mm_struct rather than mm_context_t (which is embedded into mm). This should not cause any behavioral change. Signed-off-by:
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