summaryrefslogtreecommitdiff
path: root/arch
AgeCommit message (Collapse)Author
2020-12-29powerpc/perf: Exclude kernel samples while counting events in user space.Athira Rajeev
commit aa8e21c053d72b6639ea5a7f1d3a1d0209534c94 upstream. Perf event attritube supports exclude_kernel flag to avoid sampling/profiling in supervisor state (kernel). Based on this event attr flag, Monitor Mode Control Register bit is set to freeze on supervisor state. But sometimes (due to hardware limitation), Sampled Instruction Address Register (SIAR) locks on to kernel address even when freeze on supervisor is set. Patch here adds a check to drop those samples. Cc: stable@vger.kernel.org Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1606289215-1433-1-git-send-email-atrajeev@linux.vnet.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-29um: chan_xterm: Fix fd leakAnton Ivanov
[ Upstream commit 9431f7c199ab0d02da1482d62255e0b4621cb1b5 ] xterm serial channel was leaking a fd used in setting up the port helper This bug is prehistoric - it predates switching to git. The "fixes" header here is really just to mark all the versions we would like this to apply to which is "Anything from the Cretaceous period onwards". No dinosaurs were harmed in fixing this bug. Fixes: b40997b872cd ("um: drivers/xterm.c: fix a file descriptor leak") Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com> Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-29x86/kprobes: Restore BTF if the single-stepping is cancelledMasami Hiramatsu
[ Upstream commit 78ff2733ff352175eb7f4418a34654346e1b6cd2 ] Fix to restore BTF if single-stepping causes a page fault and it is cancelled. Usually the BTF flag was restored when the single stepping is done (in resume_execution()). However, if a page fault happens on the single stepping instruction, the fault handler is invoked and the single stepping is cancelled. Thus, the BTF flag is not restored. Fixes: 1ecc798c6764 ("x86: debugctlmsr kprobes") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/160389546985.106936.12727996109376240993.stgit@devnote2 Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-29powerpc/pseries/hibernation: drop pseries_suspend_begin() from suspend opsNathan Lynch
[ Upstream commit 52719fce3f4c7a8ac9eaa191e8d75a697f9fbcbc ] There are three ways pseries_suspend_begin() can be reached: 1. When "mem" is written to /sys/power/state: kobj_attr_store() -> state_store() -> pm_suspend() -> suspend_devices_and_enter() -> pseries_suspend_begin() This never works because there is no way to supply a valid stream id using this interface, and H_VASI_STATE is called with a stream id of zero. So this call path is useless at best. 2. When a stream id is written to /sys/devices/system/power/hibernate. pseries_suspend_begin() is polled directly from store_hibernate() until the stream is in the "Suspending" state (i.e. the platform is ready for the OS to suspend execution): dev_attr_store() -> store_hibernate() -> pseries_suspend_begin() 3. When a stream id is written to /sys/devices/system/power/hibernate (continued). After #2, pseries_suspend_begin() is called once again from the pm core: dev_attr_store() -> store_hibernate() -> pm_suspend() -> suspend_devices_and_enter() -> pseries_suspend_begin() This is redundant because the VASI suspend state is already known to be Suspending. The begin() callback of platform_suspend_ops is optional, so we can simply remove that assignment with no loss of function. Fixes: 32d8ad4e621d ("powerpc/pseries: Partition hibernation support") Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201207215200.1785968-18-nathanl@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-29ARM: dts: at91: sama5d3_xplained: add pincontrol for USB HostCristian Birsan
[ Upstream commit e1062fa7292f1e3744db0a487c4ac0109e09b03d ] The pincontrol node is needed for USB Host since Linux v5.7-rc1. Without it the driver probes but VBus is not powered because of wrong pincontrol configuration. Fixes: b7c2b61570798 ("ARM: at91: add Atmel's SAMA5D3 Xplained board") Signed-off-by: Cristian Birsan <cristian.birsan@microchip.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com> Link: https://lore.kernel.org/r/20201118120019.1257580-4-cristian.birsan@microchip.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-29ARM: dts: at91: sama5d4_xplained: add pincontrol for USB HostCristian Birsan
[ Upstream commit be4dd2d448816a27c1446f8f37fce375daf64148 ] The pincontrol node is needed for USB Host since Linux v5.7-rc1. Without it the driver probes but VBus is not powered because of wrong pincontrol configuration. Fixes: 38153a017896f ("ARM: at91/dt: sama5d4: add dts for sama5d4 xplained board") Signed-off-by: Cristian Birsan <cristian.birsan@microchip.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com> Link: https://lore.kernel.org/r/20201118120019.1257580-3-cristian.birsan@microchip.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-29powerpc/feature: Fix CPU_FTRS_ALWAYS by removing CPU_FTRS_GENERIC_32Christophe Leroy
[ Upstream commit 78665179e569c7e1fe102fb6c21d0f5b6951f084 ] On 8xx, we get the following features: [ 0.000000] cpu_features = 0x0000000000000100 [ 0.000000] possible = 0x0000000000000120 [ 0.000000] always = 0x0000000000000000 This is not correct. As CONFIG_PPC_8xx is mutually exclusive with all other configurations, the three lines should be equal. The problem is due to CPU_FTRS_GENERIC_32 which is taken when CONFIG_BOOK3S_32 is NOT selected. This CPU_FTRS_GENERIC_32 is pointless because there is no generic configuration supporting all 32 bits but book3s/32. Remove this pointless generic features definition to unbreak the calculation of 'possible' features and 'always' features. Fixes: 76bc080ef5a3 ("[POWERPC] Make default cputable entries reflect selected CPU family") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/76a85f30bf981d1aeaae00df99321235494da254.1604426550.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-29MIPS: BCM47XX: fix kconfig dependency bug for BCM47XX_BCMANecip Fazil Yildiran
[ Upstream commit 3a5fe2fb9635c43359c9729352f45044f3c8df6b ] When BCM47XX_BCMA is enabled and BCMA_DRIVER_PCI is disabled, it results in the following Kbuild warning: WARNING: unmet direct dependencies detected for BCMA_DRIVER_PCI_HOSTMODE Depends on [n]: MIPS [=y] && BCMA_DRIVER_PCI [=n] && PCI_DRIVERS_LEGACY [=y] && BCMA [=y]=y Selected by [y]: - BCM47XX_BCMA [=y] && BCM47XX [=y] && PCI [=y] The reason is that BCM47XX_BCMA selects BCMA_DRIVER_PCI_HOSTMODE without depending on or selecting BCMA_DRIVER_PCI while BCMA_DRIVER_PCI_HOSTMODE depends on BCMA_DRIVER_PCI. This can also fail building the kernel. Honor the kconfig dependency to remove unmet direct dependency warnings and avoid any potential build failures. Fixes: c1d1c5d4213e ("bcm47xx: add support for bcma bus") Link: https://bugzilla.kernel.org/show_bug.cgi?id=209879 Signed-off-by: Necip Fazil Yildiran <fazilyildiran@gmail.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-29ARM: p2v: fix handling of LPAE translation in BE modeArd Biesheuvel
[ Upstream commit 4e79f0211b473f8e1eab8211a9fd50cc41a3a061 ] When running in BE mode on LPAE hardware with a PA-to-VA translation that exceeds 4 GB, we patch bits 39:32 of the offset into the wrong byte of the opcode. So fix that, by rotating the offset in r0 to the right by 8 bits, which will put the 8-bit immediate in bits 31:24. Note that this will also move bit #22 in its correct place when applying the rotation to the constant #0x400000. Fixes: d9a790df8e984 ("ARM: 7883/1: fix mov to mvn conversion in case of 64 bit phys_addr_t and BE") Acked-by: Nicolas Pitre <nico@fluxnic.net> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-29ARC: stack unwinding: don't assume non-current task is sleepingVineet Gupta
[ Upstream commit e42404fa10fd11fe72d0a0e149a321d10e577715 ] To start stack unwinding (SP, PC and BLINK) are needed. When the explicit execution context (pt_regs etc) is not available, unwinder assumes the task is sleeping (in __switch_to()) and fetches SP and BLINK from kernel mode stack. But this assumption is not true, specially in a SMP system, when top runs on 1 core, there may be active running processes on all cores. So when unwinding non courrent tasks, ensure they are NOT running. And while at it, handle the self unwinding case explicitly. This came out of investigation of a customer reported hang with rcutorture+top Link: https://github.com/foss-for-synopsys-dwc-arc-processors/linux/issues/31 Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-11x86/uprobes: Do not use prefixes.nbytes when looping over prefixes.bytesMasami Hiramatsu
commit 4e9a5ae8df5b3365183150f6df49e49dece80d8c upstream Since insn.prefixes.nbytes can be bigger than the size of insn.prefixes.bytes[] when a prefix is repeated, the proper check must be insn.prefixes.bytes[i] != 0 and i < 4 instead of using insn.prefixes.nbytes. Introduce a for_each_insn_prefix() macro for this purpose. Debugged by Kees Cook <keescook@chromium.org>. [ bp: Massage commit message, sync with the respective header in tools/ and drop "we". ] Fixes: 2b1444983508 ("uprobes, mm, x86: Add the ability to install and remove uprobes breakpoints") Reported-by: syzbot+9b64b619f10f19d19a7c@syzkaller.appspotmail.com Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/160697103739.3146288.7437620795200799020.stgit@devnote2 [sudip: adjust context, drop change of insn.h in tools] Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-11arm64: assembler: make adr_l work in modules under KASLRArd Biesheuvel
commit 41c066f2c4d436c535616fe182331766c57838f0 upstream When CONFIG_RANDOMIZE_MODULE_REGION_FULL=y, the offset between loaded modules and the core kernel may exceed 4 GB, putting symbols exported by the core kernel out of the reach of the ordinary adrp/add instruction pairs used to generate relative symbol references. So make the adr_l macro emit a movz/movk sequence instead when executing in module context. While at it, remove the pointless special case for the stack pointer. Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> [ dannf: backported to v4.4 by replacing the 3-arg adr_l macro in head.S with it's output, as this commit drops the 3-arg variant ] Fixes: c042dd600f4e ("crypto: arm64/sha - avoid non-standard inline asm tricks") Signed-off-by: dann frazier <dann.frazier@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-11powerpc: Stop exporting __clear_user which is now inlined.Michal Suchanek
Stable commit 452e2a83ea23 ("powerpc: Fix __clear_user() with KUAP enabled") redefines __clear_user as inline function but does not remove the export. Fixes: 452e2a83ea23 ("powerpc: Fix __clear_user() with KUAP enabled") Signed-off-by: Michal Suchanek <msuchanek@suse.de> Acked-by: Michael Ellerman <mpe@ellerman.id.au>
2020-12-02x86/speculation: Fix prctl() when spectre_v2_user={seccomp,prctl},ibpbAnand K Mistry
commit 33fc379df76b4991e5ae312f07bcd6820811971e upstream. When spectre_v2_user={seccomp,prctl},ibpb is specified on the command line, IBPB is force-enabled and STIPB is conditionally-enabled (or not available). However, since 21998a351512 ("x86/speculation: Avoid force-disabling IBPB based on STIBP and enhanced IBRS.") the spectre_v2_user_ibpb variable is set to SPECTRE_V2_USER_{PRCTL,SECCOMP} instead of SPECTRE_V2_USER_STRICT, which is the actual behaviour. Because the issuing of IBPB relies on the switch_mm_*_ibpb static branches, the mitigations behave as expected. Since 1978b3a53a74 ("x86/speculation: Allow IBPB to be conditionally enabled on CPUs with always-on STIBP") this discrepency caused the misreporting of IB speculation via prctl(). On CPUs with STIBP always-on and spectre_v2_user=seccomp,ibpb, prctl(PR_GET_SPECULATION_CTRL) would return PR_SPEC_PRCTL | PR_SPEC_ENABLE instead of PR_SPEC_DISABLE since both IBPB and STIPB are always on. It also allowed prctl(PR_SET_SPECULATION_CTRL) to set the IB speculation mode, even though the flag is ignored. Similarly, for CPUs without SMT, prctl(PR_GET_SPECULATION_CTRL) should also return PR_SPEC_DISABLE since IBPB is always on and STIBP is not available. [ bp: Massage commit message. ] Fixes: 21998a351512 ("x86/speculation: Avoid force-disabling IBPB based on STIBP and enhanced IBRS.") Fixes: 1978b3a53a74 ("x86/speculation: Allow IBPB to be conditionally enabled on CPUs with always-on STIBP") Signed-off-by: Anand K Mistry <amistry@google.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20201110123349.1.Id0cbf996d2151f4c143c90f9028651a5b49a5908@changeid Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-02x86/xen: don't unbind uninitialized lock_kicker_irqBrian Masney
[ Upstream commit 65cae18882f943215d0505ddc7e70495877308e6 ] When booting a hyperthreaded system with the kernel parameter 'mitigations=auto,nosmt', the following warning occurs: WARNING: CPU: 0 PID: 1 at drivers/xen/events/events_base.c:1112 unbind_from_irqhandler+0x4e/0x60 ... Hardware name: Xen HVM domU, BIOS 4.2.amazon 08/24/2006 ... Call Trace: xen_uninit_lock_cpu+0x28/0x62 xen_hvm_cpu_die+0x21/0x30 takedown_cpu+0x9c/0xe0 ? trace_suspend_resume+0x60/0x60 cpuhp_invoke_callback+0x9a/0x530 _cpu_up+0x11a/0x130 cpu_up+0x7e/0xc0 bringup_nonboot_cpus+0x48/0x50 smp_init+0x26/0x79 kernel_init_freeable+0xea/0x229 ? rest_init+0xaa/0xaa kernel_init+0xa/0x106 ret_from_fork+0x35/0x40 The secondary CPUs are not activated with the nosmt mitigations and only the primary thread on each CPU core is used. In this situation, xen_hvm_smp_prepare_cpus(), and more importantly xen_init_lock_cpu(), is not called, so the lock_kicker_irq is not initialized for the secondary CPUs. Let's fix this by exiting early in xen_uninit_lock_cpu() if the irq is not set to avoid the warning from above for each secondary CPU. Signed-off-by: Brian Masney <bmasney@redhat.com> Link: https://lore.kernel.org/r/20201107011119.631442-1-bmasney@redhat.com Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-24x86/microcode/intel: Check patch signature before saving microcode for early ↵Chen Yu
loading commit 1a371e67dc77125736cc56d3a0893f06b75855b6 upstream. Currently, scan_microcode() leverages microcode_matches() to check if the microcode matches the CPU by comparing the family and model. However, the processor stepping and flags of the microcode signature should also be considered when saving a microcode patch for early update. Use find_matching_signature() in scan_microcode() and get rid of the now-unused microcode_matches() which is a good cleanup in itself. Complete the verification of the patch being saved for early loading in save_microcode_patch() directly. This needs to be done there too because save_mc_for_early() will call save_microcode_patch() too. The second reason why this needs to be done is because the loader still tries to support, at least hypothetically, mixed-steppings systems and thus adds all patches to the cache that belong to the same CPU model albeit with different steppings. For example: microcode: CPU: sig=0x906ec, pf=0x2, rev=0xd6 microcode: mc_saved[0]: sig=0x906e9, pf=0x2a, rev=0xd6, total size=0x19400, date = 2020-04-23 microcode: mc_saved[1]: sig=0x906ea, pf=0x22, rev=0xd6, total size=0x19000, date = 2020-04-27 microcode: mc_saved[2]: sig=0x906eb, pf=0x2, rev=0xd6, total size=0x19400, date = 2020-04-23 microcode: mc_saved[3]: sig=0x906ec, pf=0x22, rev=0xd6, total size=0x19000, date = 2020-04-27 microcode: mc_saved[4]: sig=0x906ed, pf=0x22, rev=0xd6, total size=0x19400, date = 2020-04-23 The patch which is being saved for early loading, however, can only be the one which fits the CPU this runs on so do the signature verification before saving. [ bp: Do signature verification in save_microcode_patch() and rewrite commit message. ] Fixes: ec400ddeff20 ("x86/microcode_intel_early.c: Early update ucode on Intel's CPU") Signed-off-by: Chen Yu <yu.c.chen@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: stable@vger.kernel.org Link: https://bugzilla.kernel.org/show_bug.cgi?id=208535 Link: https://lkml.kernel.org/r/20201113015923.13960-1-yu.c.chen@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-24s390/cpum_sf.c: fix file permission for cpum_sfb_sizeThomas Richter
commit 78d732e1f326f74f240d416af9484928303d9951 upstream. This file is installed by the s390 CPU Measurement sampling facility device driver to export supported minimum and maximum sample buffer sizes. This file is read by lscpumf tool to display the details of the device driver capabilities. The lscpumf tool might be invoked by a non-root user. In this case it does not print anything because the file contents can not be read. Fix this by allowing read access for all users. Reading the file contents is ok, changing the file contents is left to the root user only. For further reference and details see: [1] https://github.com/ibm-s390-tools/s390-tools/issues/97 Fixes: 69f239ed335a ("s390/cpum_sf: Dynamically extend the sampling buffer if overflows occur") Cc: <stable@vger.kernel.org> # 3.14 Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Acked-by: Sumanth Korikkar <sumanthk@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-24xtensa: disable preemption around cache alias management callsMax Filippov
commit 3a860d165eb5f4d7cf0bf81ef6a5b5c5e1754422 upstream. Although cache alias management calls set up and tear down TLB entries and fast_second_level_miss is able to restore TLB entry should it be evicted they absolutely cannot preempt each other because they use the same TLBTEMP area for different purposes. Disable preemption around all cache alias management calls to enforce that. Cc: stable@vger.kernel.org Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-24powerpc/uaccess-flush: fix corenet64_smp_defconfig buildDaniel Axtens
Gunter reports problems with the corenet64_smp_defconfig: In file included from arch/powerpc/kernel/ppc_ksyms.c:10:0: arch/powerpc/include/asm/book3s/64/kup-radix.h:11:29: error: redefinition of ‘allow_user_access’ static __always_inline void allow_user_access(void __user *to, const void __user *from, ^~~~~~~~~~~~~~~~~ In file included from arch/powerpc/include/asm/uaccess.h:12:0, from arch/powerpc/kernel/ppc_ksyms.c:8: arch/powerpc/include/asm/kup.h:12:20: note: previous definition of ‘allow_user_access’ was here static inline void allow_user_access(void __user *to, const void __user *from, ^~~~~~~~~~~~~~~~~ This is because ppc_ksyms.c imports asm/book3s/64/kup-radix.h guarded by CONFIG_PPC64, rather than CONFIG_PPC_BOOK3S_64 which it should do. Fix it. Reported-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-24MIPS: Alchemy: Fix memleak in alchemy_clk_setup_cpuZhang Qilong
[ Upstream commit ac3b57adf87ad9bac7e33ca26bbbb13fae1ed62b ] If the clk_register fails, we should free h before function returns to prevent memleak. Fixes: 474402291a0ad ("MIPS: Alchemy: clock framework integration of onchip clocks") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-24ARM: dts: imx50-evk: Fix the chip select 1 IOMUXFabio Estevam
[ Upstream commit 33d0d843872c5ddbe28457a92fc6f2487315fb9f ] The SPI chip selects are represented as: cs-gpios = <&gpio4 11 GPIO_ACTIVE_LOW>, <&gpio4 13 GPIO_ACTIVE_LOW>; , which means that they are used in GPIO function instead of native SPI mode. Fix the IOMUX for the chip select 1 to use GPIO4_13 instead of the native CSPI_SSI function. Fixes: c605cbf5e135 ("ARM: dts: imx: add device tree support for Freescale imx50evk board") Signed-off-by: Fabio Estevam <festevam@gmail.com> Signed-off-by: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-24arm: dts: imx6qdl-udoo: fix rgmii phy-mode for ksz9031 phySergey Matyukevich
[ Upstream commit 7dd8f0ba88fce98e2953267a66af74c6f4792a56 ] Commit bcf3440c6dd7 ("net: phy: micrel: add phy-mode support for the KSZ9031 PHY") fixed micrel phy driver adding proper support for phy modes. Adapt imx6q-udoo board phy settings : explicitly set required delay configuration using "rgmii-id". Fixes: cbd54fe0b2bc ("ARM: dts: imx6dl-udoo: Add board support based off imx6q-udoo") Signed-off-by: Sergey Matyukevich <geomatsi@gmail.com> Reviewed-by: Fabio Estevam <festevam@gmail.com> Signed-off-by: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-24MIPS: Fix BUILD_ROLLBACK_PROLOGUE for microMIPSPaul Burton
[ Upstream commit 1eefcbc89cf3a8e252e5aeb25825594699b47360 ] When the kernel is built for microMIPS, branches targets need to be known to be microMIPS code in order to result in bit 0 of the PC being set. The branch target in the BUILD_ROLLBACK_PROLOGUE macro was simply the end of the macro, which may be pointing at padding rather than at code. This results in recent enough GNU linkers complaining like so: mips-img-linux-gnu-ld: arch/mips/built-in.o: .text+0x3e3c: Unsupported branch between ISA modes. mips-img-linux-gnu-ld: final link failed: Bad value Makefile:936: recipe for target 'vmlinux' failed make: *** [vmlinux] Error 1 Fix this by changing the branch target to be the start of the appropriate handler, skipping over any padding. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/14019/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-24arm64: psci: Avoid printing in cpu_psci_cpu_die()Will Deacon
[ Upstream commit 891deb87585017d526b67b59c15d38755b900fea ] cpu_psci_cpu_die() is called in the context of the dying CPU, which will no longer be online or tracked by RCU. It is therefore not generally safe to call printk() if the PSCI "cpu off" request fails, so remove the pr_crit() invocation. Cc: Qian Cai <cai@redhat.com> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20201106103602.9849-2-will@kernel.org Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-22KVM: x86: clflushopt should be treated as a no-op by emulationDavid Edmondson
commit 51b958e5aeb1e18c00332e0b37c5d4e95a3eff84 upstream. The instruction emulator ignores clflush instructions, yet fails to support clflushopt. Treat both similarly. Fixes: 13e457e0eebf ("KVM: x86: Emulator does not decode clflush well") Signed-off-by: David Edmondson <david.edmondson@oracle.com> Message-Id: <20201103120400.240882-1-david.edmondson@oracle.com> Reviewed-by: Joao Martins <joao.m.martins@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-22powerpc/8xx: Always fault when _PAGE_ACCESSED is not setChristophe Leroy
commit 29daf869cbab69088fe1755d9dd224e99ba78b56 upstream. The kernel expects pte_young() to work regardless of CONFIG_SWAP. Make sure a minor fault is taken to set _PAGE_ACCESSED when it is not already set, regardless of the selection of CONFIG_SWAP. This adds at least 3 instructions to the TLB miss exception handlers fast path. Following patch will reduce this overhead. Also update the rotation instruction to the correct number of bits to reflect all changes done to _PAGE_ACCESSED over time. Fixes: d069cb4373fe ("powerpc/8xx: Don't touch ACCESSED when no SWAP.") Fixes: 5f356497c384 ("powerpc/8xx: remove unused _PAGE_WRITETHRU") Fixes: e0a8e0d90a9f ("powerpc/8xx: Handle PAGE_USER via APG bits") Fixes: 5b2753fc3e8a ("powerpc/8xx: Implementation of PAGE_EXEC") Fixes: a891c43b97d3 ("powerpc/8xx: Prepare handlers for _PAGE_HUGE for 512k pages.") Cc: stable@vger.kernel.org Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/af834e8a0f1fa97bfae65664950f0984a70c4750.1602492856.git.christophe.leroy@csgroup.eu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-22powerpc/64s: flush L1D after user accessesNicholas Piggin
commit 9a32a7e78bd0cd9a9b6332cbdc345ee5ffd0c5de upstream. IBM Power9 processors can speculatively operate on data in the L1 cache before it has been completely validated, via a way-prediction mechanism. It is not possible for an attacker to determine the contents of impermissible memory using this method, since these systems implement a combination of hardware and software security measures to prevent scenarios where protected data could be leaked. However these measures don't address the scenario where an attacker induces the operating system to speculatively execute instructions using data that the attacker controls. This can be used for example to speculatively bypass "kernel user access prevention" techniques, as discovered by Anthony Steinhauser of Google's Safeside Project. This is not an attack by itself, but there is a possibility it could be used in conjunction with side-channels or other weaknesses in the privileged code to construct an attack. This issue can be mitigated by flushing the L1 cache between privilege boundaries of concern. This patch flushes the L1 cache after user accesses. This is part of the fix for CVE-2020-4788. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-22powerpc/uaccess: Evaluate macro arguments once, before user access is allowedNicholas Piggin
commit d02f6b7dab8228487268298ea1f21081c0b4b3eb upstream. get/put_user() can be called with nontrivial arguments. fs/proc/page.c has a good example: if (put_user(stable_page_flags(ppage), out)) { stable_page_flags() is quite a lot of code, including spin locks in the page allocator. Ensure these arguments are evaluated before user access is allowed. This improves security by reducing code with access to userspace, but it also fixes a PREEMPT bug with KUAP on powerpc/64s: stable_page_flags() is currently called with AMR set to allow writes, it ends up calling spin_unlock(), which can call preempt_schedule. But the task switch code can not be called with AMR set (it relies on interrupts saving the register), so this blows up. It's fine if the code inside allow_user_access() is preemptible, because a timer or IPI will save the AMR, but it's not okay to explicitly cause a reschedule. Fixes: de78a9c42a79 ("powerpc: Add a framework for Kernel Userspace Access Protection") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200407041245.600651-1-npiggin@gmail.com Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-22powerpc: Fix __clear_user() with KUAP enabledAndrew Donnellan
commit 61e3acd8c693a14fc69b824cb5b08d02cb90a6e7 upstream. The KUAP implementation adds calls in clear_user() to enable and disable access to userspace memory. However, it doesn't add these to __clear_user(), which is used in the ptrace regset code. As there's only one direct user of __clear_user() (the regset code), and the time taken to set the AMR for KUAP purposes is going to dominate the cost of a quick access_ok(), there's not much point having a separate path. Rename __clear_user() to __arch_clear_user(), and make __clear_user() just call clear_user(). Reported-by: syzbot+f25ecf4b2982d8c7a640@syzkaller-ppc64.appspotmail.com Reported-by: Daniel Axtens <dja@axtens.net> Suggested-by: Michael Ellerman <mpe@ellerman.id.au> Fixes: de78a9c42a79 ("powerpc: Add a framework for Kernel Userspace Access Protection") Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> [mpe: Use __arch_clear_user() for the asm version like arm64 & nds32] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20191209132221.15328-1-ajd@linux.ibm.com Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-22powerpc: Implement user_access_begin and friendsChristophe Leroy
commit 5cd623333e7cf4e3a334c70529268b65f2a6c2c7 upstream. Today, when a function like strncpy_from_user() is called, the userspace access protection is de-activated and re-activated for every word read. By implementing user_access_begin and friends, the protection is de-activated at the beginning of the copy and re-activated at the end. Implement user_access_begin(), user_access_end() and unsafe_get_user(), unsafe_put_user() and unsafe_copy_to_user() For the time being, we keep user_access_save() and user_access_restore() as nops. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/36d4fbf9e56a75994aca4ee2214c77b26a5a8d35.1579866752.git.christophe.leroy@c-s.fr Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-22powerpc: Add a framework for user access trackingChristophe Leroy
Backported from commit de78a9c42a79 ("powerpc: Add a framework for Kernel Userspace Access Protection"). Here we don't try to add the KUAP framework, we just want the helper functions because we want to put uaccess flush helpers in them. In terms of fixes, we don't need commit 1d8f739b07bd ("powerpc/kuap: Fix set direction in allow/prevent_user_access()") as we don't have real KUAP. Likewise as all our allows are noops and all our prevents are just flushes, we don't need commit 9dc086f1e9ef ("powerpc/futex: Fix incorrect user access blocking") The other 2 fixes we do need. The original description is: This patch implements a framework for Kernel Userspace Access Protection. Then subarches will have the possibility to provide their own implementation by providing setup_kuap() and allow/prevent_user_access(). Some platforms will need to know the area accessed and whether it is accessed from read, write or both. Therefore source, destination and size and handed over to the two functions. mpe: Rename to allow/prevent rather than unlock/lock, and add read/write wrappers. Drop the 32-bit code for now until we have an implementation for it. Add kuap to pt_regs for 64-bit as well as 32-bit. Don't split strings, use pr_crit_ratelimited(). Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Russell Currey <ruscur@russell.cc> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-22powerpc/64s: flush L1D on kernel entryNicholas Piggin
commit f79643787e0a0762d2409b7b8334e83f22d85695 upstream. IBM Power9 processors can speculatively operate on data in the L1 cache before it has been completely validated, via a way-prediction mechanism. It is not possible for an attacker to determine the contents of impermissible memory using this method, since these systems implement a combination of hardware and software security measures to prevent scenarios where protected data could be leaked. However these measures don't address the scenario where an attacker induces the operating system to speculatively execute instructions using data that the attacker controls. This can be used for example to speculatively bypass "kernel user access prevention" techniques, as discovered by Anthony Steinhauser of Google's Safeside Project. This is not an attack by itself, but there is a possibility it could be used in conjunction with side-channels or other weaknesses in the privileged code to construct an attack. This issue can be mitigated by flushing the L1 cache between privilege boundaries of concern. This patch flushes the L1 cache on kernel entry. This is part of the fix for CVE-2020-4788. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-22powerpc/64s: move some exception handlers out of lineDaniel Axtens
(backport only) We're about to grow the exception handlers, which will make a bunch of them no longer fit within the space available. We move them out of line. This is a fiddly and error-prone business, so in the interests of reviewability I haven't merged this in with the addition of the entry flush. Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-22powerpc/64s: Define MASKABLE_RELON_EXCEPTION_PSERIES_OOLDaniel Axtens
Add a definition provided by mpe and fixed up for 4.4. It doesn't exist for 4.4 and we'd quite like to use it. Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-18x86/speculation: Allow IBPB to be conditionally enabled on CPUs with ↵Anand K Mistry
always-on STIBP commit 1978b3a53a74e3230cd46932b149c6e62e832e9a upstream. On AMD CPUs which have the feature X86_FEATURE_AMD_STIBP_ALWAYS_ON, STIBP is set to on and spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT_PREFERRED At the same time, IBPB can be set to conditional. However, this leads to the case where it's impossible to turn on IBPB for a process because in the PR_SPEC_DISABLE case in ib_prctl_set() the spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT_PREFERRED condition leads to a return before the task flag is set. Similarly, ib_prctl_get() will return PR_SPEC_DISABLE even though IBPB is set to conditional. More generally, the following cases are possible: 1. STIBP = conditional && IBPB = on for spectre_v2_user=seccomp,ibpb 2. STIBP = on && IBPB = conditional for AMD CPUs with X86_FEATURE_AMD_STIBP_ALWAYS_ON The first case functions correctly today, but only because spectre_v2_user_ibpb isn't updated to reflect the IBPB mode. At a high level, this change does one thing. If either STIBP or IBPB is set to conditional, allow the prctl to change the task flag. Also, reflect that capability when querying the state. This isn't perfect since it doesn't take into account if only STIBP or IBPB is unconditionally on. But it allows the conditional feature to work as expected, without affecting the unconditional one. [ bp: Massage commit message and comment; space out statements for better readability. ] Fixes: 21998a351512 ("x86/speculation: Avoid force-disabling IBPB based on STIBP and enhanced IBRS.") Signed-off-by: Anand K Mistry <amistry@google.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lkml.kernel.org/r/20201105163246.v2.1.Ifd7243cd3e2c2206a893ad0a5b9a4f19549e22c6@changeid Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-10Revert "ARC: entry: fix potential EFA clobber when TIF_SYSCALL_TRACE"Vineet Gupta
This reverts commit 00fdec98d9881bf5173af09aebd353ab3b9ac729. (but only from 5.2 and prior kernels) The original commit was a preventive fix based on code-review and was auto-picked for stable back-port (for better or worse). It was OK for v5.3+ kernels, but turned up needing an implicit change 68e5c6f073bcf70 "(ARC: entry: EV_Trap expects r10 (vs. r9) to have exception cause)" merged in v5.3 which itself was not backported. So to summarize the stable backport of this patch for v5.2 and prior kernels is busted and it won't boot. The obvious solution is backport 68e5c6f073bcf70 but that is a pain as it doesn't revert cleanly and each of affected kernels (so far v4.19, v4.14, v4.9, v4.4) needs a slightly different massaged varaint. So the easier fix is to simply revert the backport from 5.2 and prior. The issue was not a big deal as it would cause strace to sporadically not work correctly. Waldemar Brodkorb first reported this when running ARC uClibc regressions on latest stable kernels (with offending backport). Once he bisected it, the analysis was trivial, so thx to him for this. Reported-by: Waldemar Brodkorb <wbx@uclibc-ng.org> Bisected-by: Waldemar Brodkorb <wbx@uclibc-ng.org> Cc: stable <stable@vger.kernel.org> # 5.2 and prior Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-10ARC: stack unwinding: avoid indefinite loopingVineet Gupta
commit 328d2168ca524d501fc4b133d6be076142bd305c upstream. Currently stack unwinder is a while(1) loop which relies on the dwarf unwinder to signal termination, which in turn relies on dwarf info to do so. This in theory could cause an infinite loop if the dwarf info was somehow messed up or the register contents were etc. This fix thus detects the excessive looping and breaks the loop. | Mem: 26184K used, 1009136K free, 0K shrd, 0K buff, 14416K cached | CPU: 0.0% usr 72.8% sys 0.0% nic 27.1% idle 0.0% io 0.0% irq 0.0% sirq | Load average: 4.33 2.60 1.11 2/74 139 | PID PPID USER STAT VSZ %VSZ CPU %CPU COMMAND | 133 2 root SWN 0 0.0 3 22.9 [rcu_torture_rea] | 132 2 root SWN 0 0.0 0 22.0 [rcu_torture_rea] | 131 2 root SWN 0 0.0 3 21.5 [rcu_torture_rea] | 126 2 root RW 0 0.0 2 5.4 [rcu_torture_wri] | 129 2 root SWN 0 0.0 0 0.2 [rcu_torture_fak] | 137 2 root SW 0 0.0 0 0.2 [rcu_torture_cbf] | 127 2 root SWN 0 0.0 0 0.1 [rcu_torture_fak] | 138 115 root R 1464 0.1 2 0.1 top | 130 2 root SWN 0 0.0 0 0.1 [rcu_torture_fak] | 128 2 root SWN 0 0.0 0 0.1 [rcu_torture_fak] | 115 1 root S 1472 0.1 1 0.0 -/bin/sh | 104 1 root S 1464 0.1 0 0.0 inetd | 1 0 root S 1456 0.1 2 0.0 init | 78 1 root S 1456 0.1 0 0.0 syslogd -O /var/log/messages | 134 2 root SW 0 0.0 2 0.0 [rcu_torture_sta] | 10 2 root IW 0 0.0 1 0.0 [rcu_preempt] | 88 2 root IW 0 0.0 1 0.0 [kworker/1:1-eve] | 66 2 root IW 0 0.0 2 0.0 [kworker/2:2-eve] | 39 2 root IW 0 0.0 2 0.0 [kworker/2:1-eve] | unwinder looping too long, aborting ! Cc: <stable@vger.kernel.org> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-10x86/kexec: Use up-to-dated screen_info copy to fill boot paramsKairui Song
[ Upstream commit afc18069a2cb7ead5f86623a5f3d4ad6e21f940d ] kexec_file_load() currently reuses the old boot_params.screen_info, but if drivers have change the hardware state, boot_param.screen_info could contain invalid info. For example, the video type might be no longer VGA, or the frame buffer address might be changed. If the kexec kernel keeps using the old screen_info, kexec'ed kernel may attempt to write to an invalid framebuffer memory region. There are two screen_info instances globally available, boot_params.screen_info and screen_info. Later one is a copy, and is updated by drivers. So let kexec_file_load use the updated copy. [ mingo: Tidied up the changelog. ] Signed-off-by: Kairui Song <kasong@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20201014092429.1415040-2-kasong@redhat.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-10ARM: dts: sun4i-a10: fix cpu_alert temperatureClément Péron
[ Upstream commit dea252fa41cd8ce332d148444e4799235a8a03ec ] When running dtbs_check thermal_zone warn about the temperature declared. thermal-zones: cpu-thermal:trips:cpu-alert0:temperature:0:0: 850000 is greater than the maximum of 200000 It's indeed wrong the real value is 85°C and not 850°C. Signed-off-by: Clément Péron <peron.clem@gmail.com> Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20201003100332.431178-1-peron.clem@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-10ARM: s3c24xx: fix missing system resetKrzysztof Kozlowski
commit f6d7cde84f6c5551586c8b9b68d70f8e6dc9a000 upstream. Commit f6361c6b3880 ("ARM: S3C24XX: remove separate restart code") removed usage of the watchdog reset platform code in favor of the Samsung SoC watchdog driver. However the latter was not selected thus S3C24xx platforms lost reset abilities. Cc: <stable@vger.kernel.org> Fixes: f6361c6b3880 ("ARM: S3C24XX: remove separate restart code") Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-10ARM: samsung: fix PM debug build with DEBUG_LL but !MMUKrzysztof Kozlowski
commit 7be0d19c751b02db778ca95e3274d5ea7f31891c upstream. Selecting CONFIG_SAMSUNG_PM_DEBUG (depending on CONFIG_DEBUG_LL) but without CONFIG_MMU leads to build errors: arch/arm/plat-samsung/pm-debug.c: In function ‘s3c_pm_uart_base’: arch/arm/plat-samsung/pm-debug.c:57:2: error: implicit declaration of function ‘debug_ll_addr’ [-Werror=implicit-function-declaration] Fixes: 99b2fc2b8b40 ("ARM: SAMSUNG: Use debug_ll_addr() to get UART base address") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20200910154150.3318-1-krzk@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-10arm64: berlin: Select DW_APB_TIMER_OFJisheng Zhang
commit b0fc70ce1f028e14a37c186d9f7a55e51439b83a upstream. Berlin SoCs always contain some DW APB timers which can be used as an always-on broadcast timer. Link: https://lore.kernel.org/r/20201009150536.214181fb@xhacker.debian Cc: <stable@vger.kernel.org> # v3.14+ Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-10ia64: fix build error with !COREDUMPKrzysztof Kozlowski
commit 7404840d87557c4092bf0272bce5e0354c774bf9 upstream. Fix linkage error when CONFIG_BINFMT_ELF is selected but CONFIG_COREDUMP is not: ia64-linux-ld: arch/ia64/kernel/elfcore.o: in function `elf_core_write_extra_phdrs': elfcore.c:(.text+0x172): undefined reference to `dump_emit' ia64-linux-ld: arch/ia64/kernel/elfcore.o: in function `elf_core_write_extra_data': elfcore.c:(.text+0x2b2): undefined reference to `dump_emit' Fixes: 1fcccbac89f5 ("elf coredump: replace ELF_CORE_EXTRA_* macros by functions") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20200819064146.12529-1-krzk@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-10powerpc/powernv/elog: Fix race while processing OPAL error log event.Mahesh Salgaonkar
commit aea948bb80b478ddc2448f7359d574387521a52d upstream. Every error log reported by OPAL is exported to userspace through a sysfs interface and notified using kobject_uevent(). The userspace daemon (opal_errd) then reads the error log and acknowledges the error log is saved safely to disk. Once acknowledged the kernel removes the respective sysfs file entry causing respective resources to be released including kobject. However it's possible the userspace daemon may already be scanning elog entries when a new sysfs elog entry is created by the kernel. User daemon may read this new entry and ack it even before kernel can notify userspace about it through kobject_uevent() call. If that happens then we have a potential race between elog_ack_store->kobject_put() and kobject_uevent which can lead to use-after-free of a kernfs object resulting in a kernel crash. eg: BUG: Unable to handle kernel data access on read at 0x6b6b6b6b6b6b6bfb Faulting instruction address: 0xc0000000008ff2a0 Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA PowerNV CPU: 27 PID: 805 Comm: irq/29-opal-elo Not tainted 5.9.0-rc2-gcc-8.2.0-00214-g6f56a67bcbb5-dirty #363 ... NIP kobject_uevent_env+0xa0/0x910 LR elog_event+0x1f4/0x2d0 Call Trace: 0x5deadbeef0000122 (unreliable) elog_event+0x1f4/0x2d0 irq_thread_fn+0x4c/0xc0 irq_thread+0x1c0/0x2b0 kthread+0x1c4/0x1d0 ret_from_kernel_thread+0x5c/0x6c This patch fixes this race by protecting the sysfs file creation/notification by holding a reference count on kobject until we safely send kobject_uevent(). The function create_elog_obj() returns the elog object which if used by caller function will end up in use-after-free problem again. However, the return value of create_elog_obj() function isn't being used today and there is no need as well. Hence change it to return void to make this fix complete. Fixes: 774fea1a38c6 ("powerpc/powernv: Read OPAL error log and export it through sysfs") Cc: stable@vger.kernel.org # v3.15+ Reported-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Mahesh Salgaonkar <mahesh@linux.ibm.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Reviewed-by: Oliver O'Halloran <oohall@gmail.com> Reviewed-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com> [mpe: Rework the logic to use a single return, reword comments, add oops] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20201006122051.190176-1-mpe@ellerman.id.au Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-10ARM: dts: s5pv210: remove dedicated 'audio-subsystem' nodeKrzysztof Kozlowski
[ Upstream commit 6c17a2974abf68a58517f75741b15c4aba42b4b8 ] The 'audio-subsystem' node is an artificial creation, not representing real hardware. The hardware is described by its nodes - AUDSS clock controller and I2S0. Remove the 'audio-subsystem' node along with its undocumented compatible to fix dtbs_check warnings like: audio-subsystem: $nodename:0: 'audio-subsystem' does not match '^([a-z][a-z0-9\\-]+-bus|bus|soc|axi|ahb|apb)(@[0-9a-f]+)?$' Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Tested-by: Jonathan Bakker <xc-racer2@live.ca> Link: https://lore.kernel.org/r/20200907161141.31034-9-krzk@kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-10ARM: dts: s5pv210: move PMU node out of clock controllerKrzysztof Kozlowski
[ Upstream commit bb98fff84ad1ea321823759edaba573a16fa02bd ] The Power Management Unit (PMU) is a separate device which has little common with clock controller. Moving it to one level up (from clock controller child to SoC) allows to remove fake simple-bus compatible and dtbs_check warnings like: clock-controller@e0100000: $nodename:0: 'clock-controller@e0100000' does not match '^([a-z][a-z0-9\\-]+-bus|bus|soc|axi|ahb|apb)(@[0-9a-f]+)?$' Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Tested-by: Jonathan Bakker <xc-racer2@live.ca> Link: https://lore.kernel.org/r/20200907161141.31034-8-krzk@kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-10um: change sigio_spinlock to a mutexJohannes Berg
[ Upstream commit f2d05059e15af3f70502074f4e3a504530af504a ] Lockdep complains at boot: ============================= [ BUG: Invalid wait context ] 5.7.0-05093-g46d91ecd597b #98 Not tainted ----------------------------- swapper/1 is trying to lock: 0000000060931b98 (&desc[i].request_mutex){+.+.}-{3:3}, at: __setup_irq+0x11d/0x623 other info that might help us debug this: context-{4:4} 1 lock held by swapper/1: #0: 000000006074fed8 (sigio_spinlock){+.+.}-{2:2}, at: sigio_lock+0x1a/0x1c stack backtrace: CPU: 0 PID: 1 Comm: swapper Not tainted 5.7.0-05093-g46d91ecd597b #98 Stack: 7fa4fab0 6028dfd1 0000002a 6008bea5 7fa50700 7fa50040 7fa4fac0 6028e016 7fa4fb50 6007f6da 60959c18 00000000 Call Trace: [<60023a0e>] show_stack+0x13b/0x155 [<6028e016>] dump_stack+0x2a/0x2c [<6007f6da>] __lock_acquire+0x515/0x15f2 [<6007eb50>] lock_acquire+0x245/0x273 [<6050d9f1>] __mutex_lock+0xbd/0x325 [<6050dc76>] mutex_lock_nested+0x1d/0x1f [<6008e27e>] __setup_irq+0x11d/0x623 [<6008e8ed>] request_threaded_irq+0x169/0x1a6 [<60021eb0>] um_request_irq+0x1ee/0x24b [<600234ee>] write_sigio_irq+0x3b/0x76 [<600383ca>] sigio_broken+0x146/0x2e4 [<60020bd8>] do_one_initcall+0xde/0x281 Because we hold sigio_spinlock and then get into requesting an interrupt with a mutex. Change the spinlock to a mutex to avoid that. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-10sparc64: remove mm_cpumask clearing to fix kthread_use_mm raceNicholas Piggin
[ Upstream commit bafb056ce27940c9994ea905336aa8f27b4f7275 ] The de facto (and apparently uncommented) standard for using an mm had, thanks to this code in sparc if nothing else, been that you must have a reference on mm_users *and that reference must have been obtained with mmget()*, i.e., from a thread with a reference to mm_users that had used the mm. The introduction of mmget_not_zero() in commit d2005e3f41d4 ("userfaultfd: don't pin the user memory in userfaultfd_file_create()") allowed mm_count holders to aoperate on user mappings asynchronously from the actual threads using the mm, but they were not to load those mappings into their TLB (i.e., walking vmas and page tables is okay, kthread_use_mm() is not). io_uring 2b188cc1bb857 ("Add io_uring IO interface") added code which does a kthread_use_mm() from a mmget_not_zero() refcount. The problem with this is code which previously assumed mm == current->mm and mm->mm_users == 1 implies the mm will remain single-threaded at least until this thread creates another mm_users reference, has now broken. arch/sparc/kernel/smp_64.c: if (atomic_read(&mm->mm_users) == 1) { cpumask_copy(mm_cpumask(mm), cpumask_of(cpu)); goto local_flush_and_out; } vs fs/io_uring.c if (unlikely(!(ctx->flags & IORING_SETUP_SQPOLL) || !mmget_not_zero(ctx->sqo_mm))) return -EFAULT; kthread_use_mm(ctx->sqo_mm); mmget_not_zero() could come in right after the mm_users == 1 test, then kthread_use_mm() which sets its CPU in the mm_cpumask. That update could be lost if cpumask_copy() occurs afterward. I propose we fix this by allowing mmget_not_zero() to be a first-class reference, and not have this obscure undocumented and unchecked restriction. The basic fix for sparc64 is to remove its mm_cpumask clearing code. The optimisation could be effectively restored by sending IPIs to mm_cpumask members and having them remove themselves from mm_cpumask. This is more tricky so I leave it as an exercise for someone with a sparc64 SMP. powerpc has a (currently similarly broken) example. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200914045219.3736466-4-npiggin@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-10powerpc/powernv/smp: Fix spurious DBG() warningOliver O'Halloran
[ Upstream commit f6bac19cf65c5be21d14a0c9684c8f560f2096dd ] When building with W=1 we get the following warning: arch/powerpc/platforms/powernv/smp.c: In function ‘pnv_smp_cpu_kill_self’: arch/powerpc/platforms/powernv/smp.c:276:16: error: suggest braces around empty body in an ‘if’ statement [-Werror=empty-body] 276 | cpu, srr1); | ^ cc1: all warnings being treated as errors The full context is this block: if (srr1 && !generic_check_cpu_restart(cpu)) DBG("CPU%d Unexpected exit while offline srr1=%lx!\n", cpu, srr1); When building with DEBUG undefined DBG() expands to nothing and GCC emits the warning due to the lack of braces around an empty statement. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Reviewed-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200804005410.146094-2-oohall@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-11-10powerpc/powernv/opal-dump : Use IRQ_HANDLED instead of numbers in interrupt ↵Mukesh Ojha
handler commit b29336c0e1785a28bc40a9fd47c2321671e9792e upstream. Fixes: 8034f715f ("powernv/opal-dump: Convert to irq domain") Converts all the return explicit number to a more proper IRQ_HANDLED, which looks proper incase of interrupt handler returning case. Here, It also removes error message like "nobody cared" which was getting unveiled while returning -1 or 0 from handler. Signed-off-by: Mukesh Ojha <mukesh02@linux.vnet.ibm.com> Reviewed-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Cc: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-17 00:43:20 +0000