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2020-06-30gfs2: Don't return NULL from gfs2_inode_lookupAndreas Gruenbacher
Callers expect gfs2_inode_lookup to return an inode pointer or ERR_PTR(error). Commit b66648ad6dcf caused it to return NULL instead of ERR_PTR(-ESTALE) in some cases. Fix that. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Fixes: b66648ad6dcf ("gfs2: Move inode generation number check into gfs2_inode_lookup") Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-06-30iommu: SUN50I_IOMMU should depend on HAS_DMAGeert Uytterhoeven
If NO_DMA=y (e.g. Sun-3 all{mod,yes}-config): drivers/iommu/dma-iommu.o: In function `iommu_dma_mmap': dma-iommu.c:(.text+0x92e): undefined reference to `dma_pgprot' IOMMU_DMA must not be selected, unless HAS_DMA=y. Hence fix this by making SUN50I_IOMMU depend on HAS_DMA. Fixes: 4100b8c229b32835 ("iommu: Add Allwinner H6 IOMMU driver") Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Maxime Ripard <mripard@kernel.org> Link: https://lore.kernel.org/r/20200629121146.24011-1-geert@linux-m68k.org Signed-off-by: Joerg Roedel <jroedel@suse.de>
2020-06-30Merge tag 'irqchip-fixes-5.8-1' of ↵Thomas Gleixner
git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent Pull irqchip fixes from Marc Zyngier: - Fix atomicity of affinity update in the GIC driver - Don't sleep in atomic when waiting for a GICv4.1 RD to respond - Fix a couple of typos in user-visible messages
2020-06-30iommu/sun50i: Remove unused variableMaxime Ripard
The pte_dma variable in the unmap callback is set but never used. Remove it. Fixes: 4100b8c229b3 ("iommu: Add Allwinner H6 IOMMU driver") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20200628180844.79205-2-maxime@cerno.tech Signed-off-by: Joerg Roedel <jroedel@suse.de>
2020-06-30iommu/sun50i: Change the readl timeout to the atomic variantMaxime Ripard
The flush_all_tlb call back can be called from an atomic context, so using readl_poll_timeout that embeds a udelay doesn't work. Fixes: 4100b8c229b3 ("iommu: Add Allwinner H6 IOMMU driver") Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20200628180844.79205-1-maxime@cerno.tech Signed-off-by: Joerg Roedel <jroedel@suse.de>
2020-06-30drm: sun4i: hdmi: Remove extra HPD pollingChen-Yu Tsai
The HPD sense mechanism in Allwinner's old HDMI encoder hardware is more or less an input-only GPIO. Other GPIO-based HPD implementations directly return the current state, instead of polling for a specific state and returning the other if that times out. Remove the I/O polling from sun4i_hdmi_connector_detect() and directly return a known state based on the current reading. This also gets rid of excessive CPU usage by kworker as reported on Stack Exchange [1] and Armbian forums [2]. [1] https://superuser.com/questions/1515001/debian-10-buster-on-cubietruck-with-bug-in-sun4i-drm-hdmi [2] https://forum.armbian.com/topic/14282-headless-systems-and-sun4i_drm_hdmi-a10a20/ Fixes: 9c5681011a0c ("drm/sun4i: Add HDMI support") Signed-off-by: Chen-Yu Tsai <wens@csie.org> Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://patchwork.freedesktop.org/patch/msgid/20200629060032.24134-1-wens@kernel.org
2020-06-29scsi: scsi_transport_spi: Fix function pointer checkTom Rix
clang static analysis flags several null function pointer problems. drivers/scsi/scsi_transport_spi.c:374:1: warning: Called function pointer is null (null dereference) [core.CallAndMessage] spi_transport_max_attr(offset, "%d\n"); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Reviewing the store_spi_store_max macro if (i->f->set_##field) return -EINVAL; should be if (!i->f->set_##field) return -EINVAL; Link: https://lore.kernel.org/r/20200627133242.21618-1-trix@redhat.com Reviewed-by: James Bottomley <jejb@linux.ibm.com> Signed-off-by: Tom Rix <trix@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-06-29genetlink: get rid of family->attrbufCong Wang
genl_family_rcv_msg_attrs_parse() reuses the global family->attrbuf when family->parallel_ops is false. However, family->attrbuf is not protected by any lock on the genl_family_rcv_msg_doit() code path. This leads to several different consequences, one of them is UAF, like the following: genl_family_rcv_msg_doit(): genl_start(): genl_family_rcv_msg_attrs_parse() attrbuf = family->attrbuf __nlmsg_parse(attrbuf); genl_family_rcv_msg_attrs_parse() attrbuf = family->attrbuf __nlmsg_parse(attrbuf); info->attrs = attrs; cb->data = info; netlink_unicast_kernel(): consume_skb() genl_lock_dumpit(): genl_dumpit_info(cb)->attrs Note family->attrbuf is an array of pointers to the skb data, once the skb is freed, any dereference of family->attrbuf will be a UAF. Maybe we could serialize the family->attrbuf with genl_mutex too, but that would make the locking more complicated. Instead, we can just get rid of family->attrbuf and always allocate attrbuf from heap like the family->parallel_ops==true code path. This may add some performance overhead but comparing with taking the global genl_mutex, it still looks better. Fixes: 75cdbdd08900 ("net: ieee802154: have genetlink code to parse the attrs during dumpit") Fixes: 057af7071344 ("net: tipc: have genetlink code to parse the attrs during dumpit") Reported-and-tested-by: syzbot+3039ddf6d7b13daf3787@syzkaller.appspotmail.com Reported-and-tested-by: syzbot+80cad1e3cb4c41cde6ff@syzkaller.appspotmail.com Reported-and-tested-by: syzbot+736bcbcb11b60d0c0792@syzkaller.appspotmail.com Reported-and-tested-by: syzbot+520f8704db2b68091d44@syzkaller.appspotmail.com Reported-and-tested-by: syzbot+c96e4dfb32f8987fdeed@syzkaller.appspotmail.com Cc: Jiri Pirko <jiri@mellanox.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-29Merge tag 'mac80211-for-net-2020-06-29' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211 Johannes Berg says: ==================== Couple of fixes/small things: * TX control port status check fixed to not assume frame format * mesh control port fixes * error handling/leak fixes when starting AP, with HE attributes * fix broadcast packet handling with encapsulation offload * add new AKM suites * and a small code cleanup ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-29arm/xen: remove the unused macro GRANT_TABLE_PHYSADDRXiaofei Tan
Fix the following sparse warning: arch/arm64/xen/../../arm/xen/enlighten.c:244: warning: macro "GRANT_TABLE_PHYSADDR" is not used [-Wunused-macros] It is an isolated macro, and should be removed when its last user was deleted in the following commit 3cf4095d7446 ("arm/xen: Use xen_xlate_map_ballooned_pages to setup grant table") Signed-off-by: Xiaofei Tan <tanxiaofei@huawei.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
2020-06-29ARM: dts: meson: Align L2 cache-controller nodename with dtschemaKrzysztof Kozlowski
Fix dtschema validator warnings like: l2-cache-controller@c4200000: $nodename:0: 'l2-cache-controller@c4200000' does not match '^(cache-controller|cpu)(@[0-9a-f,]+)*$' Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Kevin Hilman <khilman@baylibre.com> Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Link: https://lore.kernel.org/r/20200626080626.4080-1-krzk@kernel.org
2020-06-29arm64: dts: meson-gxl-s805x: reduce initial Mali450 core frequencyNeil Armstrong
When starting at 744MHz, the Mali 450 core crashes on S805X based boards: lima d00c0000.gpu: IRQ ppmmu3 not found lima d00c0000.gpu: IRQ ppmmu4 not found lima d00c0000.gpu: IRQ ppmmu5 not found lima d00c0000.gpu: IRQ ppmmu6 not found lima d00c0000.gpu: IRQ ppmmu7 not found Internal error: synchronous external abort: 96000210 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.7.2+ #492 Hardware name: Libre Computer AML-S805X-AC (DT) pstate: 40000005 (nZcv daif -PAN -UAO) pc : lima_gp_init+0x28/0x188 ... Call trace: lima_gp_init+0x28/0x188 lima_device_init+0x334/0x534 lima_pdev_probe+0xa4/0xe4 ... Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b Reverting to a safer 666Mhz frequency on the S805X that doesn't use the GP0 PLL makes it more stable. Fixes: fd47716479f5 ("ARM64: dts: add S805X based P241 board") Fixes: 0449b8e371ac ("arm64: dts: meson: add libretech aml-s805x-ac board") Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Kevin Hilman <khilman@baylibre.com> Link: https://lore.kernel.org/r/20200618132737.14243-1-narmstrong@baylibre.com
2020-06-29arm64: dts: meson: add missing gxl rng clockJerome Brunet
The peripheral clock of the RNG is missing for gxl while it is present for gxbb. Fixes: 1b3f6d148692 ("ARM64: dts: meson-gx: add clock CLKID_RNG0 to hwrng node") Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> Signed-off-by: Kevin Hilman <khilman@baylibre.com> Reviewed-by: Neil Armstrong <narmstrong@baylibre.com> Link: https://lore.kernel.org/r/20200617125346.1163527-1-jbrunet@baylibre.com
2020-06-29soc: amlogic: meson-gx-socinfo: Fix S905X3 and S905D3 ID'sChristian Hewitt
Correct the SoC revision and package bits/mask values for S905D3/X3 to detect a wider range of observed SoC IDs, and tweak sort order for A311D/S922X. S905X3 05 0000 0101 (SEI610 initial devices) S905X3 10 0001 0000 (ODROID-C4 and recent Android boxes) S905X3 50 0101 0000 (SEI610 later revisions) S905D3 04 0000 0100 (VIM3L devices in kernelci) S905D3 b0 1011 0000 (VIM3L initial production) Fixes commit c9cc9bec36d0 ("soc: amlogic: meson-gx-socinfo: Add SM1 and S905X3 IDs") Suggested-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Christian Hewitt <christianshewitt@gmail.com> Signed-off-by: Kevin Hilman <khilman@baylibre.com> Acked-by: Neil Armstrong <narmstrong@baylibre.com> Link: https://lore.kernel.org/r/20200609081318.28023-1-christianshewitt@gmail.com
2020-06-29selftests: tpm: Use /bin/sh instead of /bin/bashJarkko Sakkinen
It's better to use /bin/sh instead of /bin/bash in order to run the tests in the BusyBox shell. Fixes: 6ea3dfe1e073 ("selftests: add TPM 2.0 tests") Cc: stable@vger.kernel.org Cc: linux-integrity@vger.kernel.org Cc: linux-kselftest@vger.kernel.org Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-06-29selftests: tpm: Use 'test -e' instead of 'test -f'Jarkko Sakkinen
'test -f' is suitable only for *regular* files. Use 'test -e' instead. Cc: Nikita Sobolev <Nikita.Sobolev@synopsys.com> Cc: linux-integrity@vger.kernel.org Cc: linux-kselftest@vger.kernel.org Fixes: 5627f9cffee7 ("Kernel selftests: Add check if TPM devices are supported") Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-06-29Revert "tpm: selftest: cleanup after unseal with wrong auth/policy test"Jarkko Sakkinen
The reverted commit illegitly uses tpm2-tools. External dependencies are absolutely forbidden from these tests. There is also the problem that clearing is not necessarily wanted behavior if the test/target computer is not used only solely for testing. Fixes: a9920d3bad40 ("tpm: selftest: cleanup after unseal with wrong auth/policy test") Cc: Tadeusz Struk <tadeusz.struk@intel.com> Cc: stable@vger.kernel.org Cc: linux-integrity@vger.kernel.org Cc: linux-kselftest@vger.kernel.org Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-06-29ASoC: rt5670: Fix dac- and adc- vol-tlv values being off by a factor of 10Hans de Goede
The adc_vol_tlv volume-control has a range from -17.625 dB to +30 dB, not -176.25 dB to + 300 dB. This wrong scale is esp. a problem in userspace apps which translate the dB scale to a linear scale. With the logarithmic dB scale being of by a factor of 10 we loose all precision in the lower area of the range when apps translate things to a linear scale. E.g. the 0 dB default, which corresponds with a value of 47 of the 0 - 127 range for the control, would be shown as 0/100 in alsa-mixer. Since the centi-dB values used in the TLV struct cannot represent the 0.375 dB step size used by these controls, change the TLV definition for them to specify a min and max value instead of min + stepsize. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20200628155231.71089-5-hdegoede@redhat.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-06-29ASoC: rt5670: Add new gpio1_is_ext_spk_en quirk and enable it on the Lenovo ↵Hans de Goede
Miix 2 10 The Lenovo Miix 2 10 has a keyboard dock with extra speakers in the dock. Rather then the ACL5672's GPIO1 pin being used as IRQ to the CPU, it is actually used to enable the amplifier for these speakers (the IRQ to the CPU comes directly from the jack-detect switch). Add a quirk for having an ext speaker-amplifier enable pin on GPIO1 and replace the Lenovo Miix 2 10's dmi_system_id table entry's wrong GPIO_DEV quirk (which needs to be renamed to GPIO1_IS_IRQ) with the new RT5670_GPIO1_IS_EXT_SPK_EN quirk, so that we enable the external speaker-amplifier as necessary. Also update the ident field for the dmi_system_id table entry, the Miix models are not Thinkpads. Fixes: 67e03ff3f32f ("ASoC: codecs: rt5670: add Thinkpad Tablet 10 quirk") Signed-off-by: Hans de Goede <hdegoede@redhat.com> BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1786723 Link: https://lore.kernel.org/r/20200628155231.71089-4-hdegoede@redhat.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-06-29ASoC: rt5670: Correct RT5670_LDO_SEL_MASKHans de Goede
The RT5670_PWR_ANLG1 register has 3 bits to select the LDO voltage, so the correct mask is 0x7 not 0x3. Because of this wrong mask we were programming the ldo bits to a setting of binary 001 (0x05 & 0x03) instead of binary 101 when moving to SND_SOC_BIAS_PREPARE. According to the datasheet 001 is a reserved value, so no idea what it did, since the driver was working fine before I guess we got lucky and it does something which is ok. Fixes: 5e8351de740d ("ASoC: add RT5670 CODEC driver") Signed-off-by: Hans de Goede <hdegoede@redhat.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200628155231.71089-3-hdegoede@redhat.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-06-29ASoC: Intel: cht_bsw_rt5672: Change bus format to I2S 2 channelHans de Goede
The default mode for SSP configuration is TDM 4 slot and so far we were using this for the bus format on cht-bsw-rt56732 boards. One board, the Lenovo Miix 2 10 uses not 1 but 2 codecs connected to SSP2. The second piggy-backed, output-only codec is inside the keyboard-dock (which has extra speakers). Unlike the main rt5672 codec, we cannot configure this codec, it is hard coded to use 2 channel 24 bit I2S. Using 4 channel TDM leads to the dock speakers codec (which listens in on the data send from the SSP to the rt5672 codec) emiting horribly distorted sound. Since we only support 2 channels anyways, there is no need for TDM on any cht-bsw-rt5672 designs. So we can simply use I2S 2ch everywhere. This commit fixes the Lenovo Miix 2 10 dock speakers issue by changing the bus format set in cht_codec_fixup() to I2S 2 channel. This change has been tested on the following devices with a rt5672 codec: Lenovo Miix 2 10 Lenovo Thinkpad 8 Lenovo Thinkpad 10 (gen 1) Signed-off-by: Hans de Goede <hdegoede@redhat.com> Cc: stable@vger.kernel.org BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1786723 Link: https://lore.kernel.org/r/20200628155231.71089-2-hdegoede@redhat.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-06-29block/keyslot-manager: use kvfree_sensitive()Eric Biggers
Make blk_ksm_destroy() use the kvfree_sensitive() function (which was introduced in v5.8-rc1) instead of open-coding it. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-29Documentation/litmus-tests: Add note on herd7 7.56 in atomic litmus testAkira Yokosawa
herdtools 7.56 has enhanced herd7's C parser so that the "(void)expr" construct in Atomic-RMW-ops-are-atomic-WRT-atomic_set.litmus is accepted. This is independent of LKMM's cat model, so mention the required version in the header of the litmus test and its entry in README. CC: Boqun Feng <boqun.feng@gmail.com> Reported-by: Andrea Parri <parri.andrea@gmail.com> Acked-by: Andrea Parri <parri.andrea@gmail.com> Signed-off-by: Akira Yokosawa <akiyks@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29tools/memory-model/README: Mention herdtools7 7.56 in compatibility tableAkira Yokosawa
herdtools7 7.56 is going to be released in the week of 22 Jun 2020. This commit therefore adds the exact version in the compatibility table. Acked-by: Andrea Parri <parri.andrea@gmail.com> Signed-off-by: Akira Yokosawa <akiyks@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29tools/memory-model/README: Expand dependency of klitmus7Akira Yokosawa
klitmus7 is independent of the memory model but depends on the build-target kernel release. It occasionally lost compatibility due to kernel API changes [1, 2, 3]. It was remedied in a backwards-compatible manner respectively [4, 5, 6]. Reflect this fact in README. [1]: b899a850431e ("compiler.h: Remove ACCESS_ONCE()") [2]: 0bb95f80a38f ("Makefile: Globally enable VLA warning") [3]: d56c0d45f0e2 ("proc: decouple proc from VFS with "struct proc_ops"") [4]: https://github.com/herd/herdtools7/commit/e87d7f9287d1 ("klitmus: Use WRITE_ONCE and READ_ONCE in place of deprecated ACCESS_ONCE") [5]: https://github.com/herd/herdtools7/commit/a0cbb10d02be ("klitmus: Avoid variable length array") [6]: https://github.com/herd/herdtools7/commit/46b9412d3a58 ("klitmus: Linux kernel v5.6.x compat") NOTE: [5] was ahead of herdtools7 7.53, which did not make an official release. Code generated by klitmus7 without [5] can still be built targeting Linux 4.20--5.5 if you don't care VLA warnings. Acked-by: Andrea Parri <parri.andrea@gmail.com> Signed-off-by: Akira Yokosawa <akiyks@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29Documentation/litmus-tests: Cite an RCU litmus testJoel Fernandes (Google)
This commit cites a pertinent RCU-related litmus test. Co-developed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Co-developed-by: Akira Yokosawa <akiyks@gmail.com> [Alan: grammar nit] [ paulmck: Update commit log and title per Akira feedback. ] Suggested-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Akira Yokosawa <akiyks@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29Documentation/litmus-tests: Merge atomic's README into top-level oneAkira Yokosawa
Where Documentation/litmus-tests/README lists RCU litmus tests, Documentation/litmus-tests/atomic/README lists atomic litmus tests. For symmetry, merge the latter into former, with some context adjustment in the introduction. Acked-by: Andrea Parri <parri.andrea@gmail.com> Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org> Acked-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Akira Yokosawa <akiyks@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29tools/memory-model: Fix reference to litmus test in recipes.txtAkira Yokosawa
The name of litmus test doesn't match the one described below. Fix the name of litmus test. Acked-by: Andrea Parri <parri.andrea@gmail.com> Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Akira Yokosawa <akiyks@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29Documentation/litmus-tests/atomic: Add a test for smp_mb__after_atomic()Boqun Feng
We already use a litmus test in atomic_t.txt to describe atomic RMW + smp_mb__after_atomic() is stronger than acquire (both the read and the write parts are ordered). So make it a litmus test in atomic-tests directory, so that people can access the litmus easily. Additionally, change the processor numbers "P1, P2" to "P0, P1" in atomic_t.txt for the consistency with the processor numbers in the litmus test, which herd can handle. Acked-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Andrea Parri <parri.andrea@gmail.com> Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29Documentation/litmus-tests/atomic: Add a test for atomic_set()Boqun Feng
We already use a litmus test in atomic_t.txt to describe the behavior of an atomic_set() with the an atomic RMW, so add it into atomic-tests directory to make it easily accessible for anyone who cares about the semantics of our atomic APIs. Besides currently the litmus test "atomic-set" in atomic_t.txt has a few things to be improved: 1) The CPU/Processor numbers "P1,P2" are not only inconsistent with the rest of the document, which uses "CPU0" and "CPU1", but also unacceptable by the herd tool, which requires processors start at "P0". 2) The initialization block uses a "atomic_set()", which is OK, but it's better to use ATOMIC_INIT() to make clear this is an initialization. 3) The return value of atomic_add_unless() is discarded inexplicitly, which is OK for C language, but it will be helpful to the herd tool if we use a void cast to make the discard explicit. 4) The name and the paragraph describing the test need to be more accurate and aligned with our wording in LKMM. Therefore fix these in both atomic_t.txt and the new added litmus test. Acked-by: Andrea Parri <parri.andrea@gmail.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29Documentation/litmus-tests: Introduce atomic directoryBoqun Feng
Although we have atomic_t.txt and its friends to describe the semantics of atomic APIs and lib/atomic64_test.c for build testing and testing in UP mode, the tests for our atomic APIs in real SMP mode are still missing. Since now we have the LKMM tool in kernel and litmus tests can be used to generate kernel modules for testing purpose with "klitmus" (a tool from the LKMM toolset), it makes sense to put a few typical litmus tests into kernel so that 1) they are the examples to describe the conceptual mode of the semantics of atomic APIs, and 2) they can be used to generate kernel test modules for anyone who is interested to test the atomic APIs implementation (in most cases, is the one who implements the APIs for a new arch) Therefore, introduce the atomic directory for this purpose. The directory is maintained by the LKMM group to make sure the litmus tests are always aligned with our memory model. Acked-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Andrea Parri <parri.andrea@gmail.com> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29tools/memory-model: Add an exception for limitations on _unless() familyBoqun Feng
According to Luc, atomic_add_unless() is directly provided by herd7, therefore it can be used in litmus tests. So change the limitation section in README to unlimit the use of atomic_add_unless(). Cc: Luc Maranget <luc.maranget@inria.fr> Acked-by: Andrea Parri <parri.andrea@gmail.com> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29MAINTAINERS: Update maintainers for new Documentation/litmus-testsJoel Fernandes (Google)
This commit adds Joel Fernandes as official LKMM reviewer. Acked-by: Boqun Feng <boqun.feng@gmail.com> Acked-by: Andrea Parri <parri.andrea@gmail.com> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> [ paulmck: Apply Joe Perches alphabetization feedback. ] Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29Documentation: LKMM: Add litmus test for RCU GP guarantee where reader storesJoel Fernandes (Google)
This adds an example for the important RCU grace period guarantee, which shows an RCU reader can never span a grace period. Acked-by: Andrea Parri <parri.andrea@gmail.com> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29Documentation: LKMM: Add litmus test for RCU GP guarantee where updater ↵Joel Fernandes (Google)
frees object This adds an example for the important RCU grace period guarantee, which shows an RCU reader can never span a grace period. Acked-by: Andrea Parri <parri.andrea@gmail.com> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29tools/memory-model: Fix "conflict" definitionMarco Elver
The definition of "conflict" should not include the type of access nor whether the accesses are concurrent or not, which this patch addresses. The definition of "data race" remains unchanged. The definition of "conflict" as we know it and is cited by various papers on memory consistency models appeared in [1]: "Two accesses to the same variable conflict if at least one is a write; two operations conflict if they execute conflicting accesses." The LKMM as well as the C11 memory model are adaptations of data-race-free, which are based on the work in [2]. Necessarily, we need both conflicting data operations (plain) and synchronization operations (marked). For example, C11's definition is based on [3], which defines a "data race" as: "Two memory operations conflict if they access the same memory location, and at least one of them is a store, atomic store, or atomic read-modify-write operation. In a sequentially consistent execution, two memory operations from different threads form a type 1 data race if they conflict, at least one of them is a data operation, and they are adjacent in <T (i.e., they may be executed concurrently)." [1] D. Shasha, M. Snir, "Efficient and Correct Execution of Parallel Programs that Share Memory", 1988. URL: http://snir.cs.illinois.edu/listed/J21.pdf [2] S. Adve, "Designing Memory Consistency Models for Shared-Memory Multiprocessors", 1993. URL: http://sadve.cs.illinois.edu/Publications/thesis.pdf [3] H.-J. Boehm, S. Adve, "Foundations of the C++ Concurrency Memory Model", 2008. URL: https://www.hpl.hp.com/techreports/2008/HPL-2008-56.pdf Signed-off-by: Marco Elver <elver@google.com> Co-developed-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Andrea Parri <parri.andrea@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29tools/memory-model: Add recent referencesPaul E. McKenney
This commit updates the list of LKMM-related publications in Documentation/references.txt. Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Acked-by: Andrea Parri <parri.andrea@gmail.com>
2020-06-29kcsan: Disable branch tracing in core runtimeMarco Elver
Disable branch tracing in core KCSAN runtime if branches are being traced (TRACE_BRANCH_PROFILING). This it to avoid its performance impact, but also avoid recursion in case KCSAN is enabled for the branch tracing runtime. The latter had already been a problem for KASAN: https://lore.kernel.org/lkml/CANpmjNOeXmD5E3O50Z3MjkiuCYaYOPyi+1rq=GZvEKwBvLR0Ug@mail.gmail.com/ Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29kcsan: Simplify compiler flagsMarco Elver
Simplify the set of compiler flags for the runtime by removing cc-option from -fno-stack-protector, because all supported compilers support it. This saves us one compiler invocation during build. Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29kcsan: Re-add GCC as a supported compilerMarco Elver
GCC version 11 recently implemented all requirements to correctly support KCSAN: 1. Correct no_sanitize-attribute inlining behaviour: https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=4089df8ef4a63126b0774c39b6638845244c20d2 2. --param=tsan-distinguish-volatile https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=ab2789ec507a94f1a75a6534bca51c7b39037ce0 3. --param=tsan-instrument-func-entry-exit https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=06712fc68dc9843d9af7c7ac10047f49d305ad76 Therefore, we can re-enable GCC for KCSAN, and document the new compiler requirements. Signed-off-by: Marco Elver <elver@google.com> Cc: Martin Liska <mliska@suse.cz> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29kcsan: Add jiffies test to test suiteMarco Elver
Add a test that KCSAN nor the compiler gets confused about accesses to jiffies on different architectures. Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29kcsan: Remove existing special atomic rulesMarco Elver
Remove existing special atomic rules from kcsan_is_atomic_special() because they are no longer needed. Since we rely on the compiler emitting instrumentation distinguishing volatile accesses, the rules have become redundant. Let's keep kcsan_is_atomic_special() around, so that we have an obvious place to add special rules should the need arise in future. Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29kcsan: Rename test.c to selftest.cMarco Elver
Rename 'test.c' to 'selftest.c' to better reflect its purpose (Kconfig variable and code inside already match this). This is to avoid confusion with the test suite module in 'kcsan-test.c'. No functional change. Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29kcsan: Silence -Wmissing-prototypes warning with W=1Marco Elver
The functions here should not be forward declared for explicit use elsewhere in the kernel, as they should only be emitted by the compiler due to sanitizer instrumentation. Add forward declarations a line above their definition to shut up warnings in W=1 builds. Link: https://lkml.kernel.org/r/202006060103.jSCpnV1g%lkp@intel.com Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29kcsan: Prefer '__no_kcsan inline' in testMarco Elver
Instead of __no_kcsan_or_inline, prefer '__no_kcsan inline' in test -- this is in case we decide to remove __no_kcsan_or_inline. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29locking/osq_lock: Annotate a data race in osq_lockQian Cai
The prev->next pointer can be accessed concurrently as noticed by KCSAN: write (marked) to 0xffff9d3370dbbe40 of 8 bytes by task 3294 on cpu 107: osq_lock+0x25f/0x350 osq_wait_next at kernel/locking/osq_lock.c:79 (inlined by) osq_lock at kernel/locking/osq_lock.c:185 rwsem_optimistic_spin <snip> read to 0xffff9d3370dbbe40 of 8 bytes by task 3398 on cpu 100: osq_lock+0x196/0x350 osq_lock at kernel/locking/osq_lock.c:157 rwsem_optimistic_spin <snip> Since the write only stores NULL to prev->next and the read tests if prev->next equals to this_cpu_ptr(&osq_node). Even if the value is shattered, the code is still working correctly. Thus, mark it as an intentional data race using the data_race() macro. Signed-off-by: Qian Cai <cai@lca.pw> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29kcsan: Add test suiteMarco Elver
This adds KCSAN test focusing on behaviour of the integrated runtime. Tests various race scenarios, and verifies the reports generated to console. Makes use of KUnit for test organization, and the Torture framework for test thread control. Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29rculist: Add ASSERT_EXCLUSIVE_ACCESS() to __list_splice_init_rcu()Paul E. McKenney
After the sync() in __list_splice_init_rcu(), there should be no readers traversing the old list. This commit therefore enlists the help of KCSAN to verify this condition via a pair of calls to ASSERT_EXCLUSIVE_ACCESS(). Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Cc: Marco Elver <elver@google.com>
2020-06-29x86/mm/pat: Mark an intentional data raceQian Cai
cpa_4k_install could be accessed concurrently as noticed by KCSAN, read to 0xffffffffaa59a000 of 8 bytes by interrupt on cpu 7: cpa_inc_4k_install arch/x86/mm/pat/set_memory.c:131 [inline] __change_page_attr+0x10cf/0x1840 arch/x86/mm/pat/set_memory.c:1514 __change_page_attr_set_clr+0xce/0x490 arch/x86/mm/pat/set_memory.c:1636 __set_pages_np+0xc4/0xf0 arch/x86/mm/pat/set_memory.c:2148 __kernel_map_pages+0xb0/0xc8 arch/x86/mm/pat/set_memory.c:2178 kernel_map_pages include/linux/mm.h:2719 [inline] <snip> write to 0xffffffffaa59a000 of 8 bytes by task 1 on cpu 6: cpa_inc_4k_install arch/x86/mm/pat/set_memory.c:131 [inline] __change_page_attr+0x10ea/0x1840 arch/x86/mm/pat/set_memory.c:1514 __change_page_attr_set_clr+0xce/0x490 arch/x86/mm/pat/set_memory.c:1636 __set_pages_p+0xc4/0xf0 arch/x86/mm/pat/set_memory.c:2129 __kernel_map_pages+0x2e/0xc8 arch/x86/mm/pat/set_memory.c:2176 kernel_map_pages include/linux/mm.h:2719 [inline] <snip> Both accesses are due to the same "cpa_4k_install++" in cpa_inc_4k_install. A data race here could be potentially undesirable: depending on compiler optimizations or how x86 executes a non-LOCK'd increment, it may lose increments, corrupt the counter, etc. Since this counter only seems to be used for printing some stats, this data race itself is unlikely to cause harm to the system though. Thus, mark this intentional data race using the data_race() marco. Suggested-by: Macro Elver <elver@google.com> Signed-off-by: Qian Cai <cai@lca.pw> Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29fork: Annotate a data race in vm_area_dup()Qian Cai
struct vm_area_struct could be accessed concurrently as noticed by KCSAN, write to 0xffff9cf8bba08ad8 of 8 bytes by task 14263 on cpu 35: vma_interval_tree_insert+0x101/0x150: rb_insert_augmented_cached at include/linux/rbtree_augmented.h:58 (inlined by) vma_interval_tree_insert at mm/interval_tree.c:23 __vma_link_file+0x6e/0xe0 __vma_link_file at mm/mmap.c:629 vma_link+0xa2/0x120 mmap_region+0x753/0xb90 do_mmap+0x45c/0x710 vm_mmap_pgoff+0xc0/0x130 ksys_mmap_pgoff+0x1d1/0x300 __x64_sys_mmap+0x33/0x40 do_syscall_64+0x91/0xc44 entry_SYSCALL_64_after_hwframe+0x49/0xbe read to 0xffff9cf8bba08a80 of 200 bytes by task 14262 on cpu 122: vm_area_dup+0x6a/0xe0 vm_area_dup at kernel/fork.c:362 __split_vma+0x72/0x2a0 __split_vma at mm/mmap.c:2661 split_vma+0x5a/0x80 mprotect_fixup+0x368/0x3f0 do_mprotect_pkey+0x263/0x420 __x64_sys_mprotect+0x51/0x70 do_syscall_64+0x91/0xc44 entry_SYSCALL_64_after_hwframe+0x49/0xbe vm_area_dup() blindly copies all fields of original VMA to the new one. This includes coping vm_area_struct::shared.rb which is normally protected by i_mmap_lock. But this is fine because the read value will be overwritten on the following __vma_link_file() under proper protection. Thus, mark it as an intentional data race and insert a few assertions for the fields that should not be modified concurrently. Signed-off-by: Qian Cai <cai@lca.pw> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>