kernel/arch/arm/include, branch linux-5.1.y

ARM: prevent tracing IPI_CPU_BACKTRACE

2019-06-15T09:52:51Z

[ Upstream commit be167862ae7dd85c56d385209a4890678e1b0488 ] Patch series "compiler: allow all arches to enable CONFIG_OPTIMIZE_INLINING", v3. This patch (of 11): When function tracing for IPIs is enabled, we get a warning for an overflow of the ipi_types array with the IPI_CPU_BACKTRACE type as triggered by raise_nmi(): arch/arm/kernel/smp.c: In function 'raise_nmi': arch/arm/kernel/smp.c:489:2: error: array subscript is above array bounds [-Werror=array-bounds] trace_ipi_raise(target, ipi_types[ipinr]); This is a correct warning as we actually overflow the array here. This patch raise_nmi() to call __smp_cross_call() instead of smp_cross_call(), to avoid calling into ftrace. For clarification, I'm also adding a two new code comments describing how this one is special. The warning appears to have shown up after commit e7273ff49acf ("ARM: 8488/1: Make IPI_CPU_BACKTRACE a "non-secure" SGI"), which changed the number assignment from '15' to '8', but as far as I can tell has existed since the IPI tracepoints were first introduced. If we decide to backport this patch to stable kernels, we probably need to backport e7273ff49acf as well. [yamada.masahiro@socionext.com: rebase on v5.1-rc1] Link: http://lkml.kernel.org/r/20190423034959.13525-2-yamada.masahiro@socionext.com Fixes: e7273ff49acf ("ARM: 8488/1: Make IPI_CPU_BACKTRACE a "non-secure" SGI") Fixes: 365ec7b17327 ("ARM: add IPI tracepoints") # v3.17 Signed-off-by: Arnd Bergmann Signed-off-by: Masahiro Yamada Cc: Heiko Carstens Cc: Arnd Bergmann Cc: Ingo Molnar Cc: Christophe Leroy Cc: Mathieu Malaterre Cc: "H. Peter Anvin" Cc: Thomas Gleixner Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Ralf Baechle Cc: Stefan Agner Cc: Boris Brezillon Cc: Miquel Raynal Cc: Richard Weinberger Cc: David Woodhouse Cc: Brian Norris Cc: Marek Vasut Cc: Russell King Cc: Borislav Petkov Cc: Mark Rutland Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

ARM: vdso: Remove dependency with the arch_timer driver internals

2019-05-31T13:43:18Z

[ Upstream commit 1f5b62f09f6b314c8d70b9de5182dae4de1f94da ] The VDSO code uses the kernel helper that was originally designed to abstract the access between 32 and 64bit systems. It worked so far because this function is declared as 'inline'. As we're about to revamp that part of the code, the VDSO would break. Let's fix it by doing what should have been done from the start, a proper system register access. Reviewed-by: Mark Rutland Signed-off-by: Marc Zyngier Signed-off-by: Will Deacon Signed-off-by: Sasha Levin

syscalls: Remove start and number from syscall_set_arguments() args

2019-04-05T13:27:23Z

After removing the start and count arguments of syscall_get_arguments() it seems reasonable to remove them from syscall_set_arguments(). Note, as of today, there are no users of syscall_set_arguments(). But we are told that there will be soon. But for now, at least make it consistent with syscall_get_arguments(). Link: http://lkml.kernel.org/r/20190327222014.GA32540@altlinux.org Cc: Oleg Nesterov Cc: Kees Cook Cc: Andy Lutomirski Cc: Dominik Brodowski Cc: Dave Martin Cc: "Dmitry V. Levin" Cc: x86@kernel.org Cc: linux-snps-arc@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-c6x-dev@linux-c6x.org Cc: uclinux-h8-devel@lists.sourceforge.jp Cc: linux-hexagon@vger.kernel.org Cc: linux-ia64@vger.kernel.org Cc: linux-mips@vger.kernel.org Cc: nios2-dev@lists.rocketboards.org Cc: openrisc@lists.librecores.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-riscv@lists.infradead.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: sparclinux@vger.kernel.org Cc: linux-um@lists.infradead.org Cc: linux-xtensa@linux-xtensa.org Cc: linux-arch@vger.kernel.org Acked-by: Max Filippov # For xtensa changes Acked-by: Will Deacon # For the arm64 bits Reviewed-by: Thomas Gleixner # for x86 Reviewed-by: Dmitry V. Levin Signed-off-by: Steven Rostedt (VMware)

syscalls: Remove start and number from syscall_get_arguments() args

2019-04-05T13:26:43Z

At Linux Plumbers, Andy Lutomirski approached me and pointed out that the function call syscall_get_arguments() implemented in x86 was horribly written and not optimized for the standard case of passing in 0 and 6 for the starting index and the number of system calls to get. When looking at all the users of this function, I discovered that all instances pass in only 0 and 6 for these arguments. Instead of having this function handle different cases that are never used, simply rewrite it to return the first 6 arguments of a system call. This should help out the performance of tracing system calls by ptrace, ftrace and perf. Link: http://lkml.kernel.org/r/20161107213233.754809394@goodmis.org Cc: Oleg Nesterov Cc: Kees Cook Cc: Andy Lutomirski Cc: Dominik Brodowski Cc: Dave Martin Cc: "Dmitry V. Levin" Cc: x86@kernel.org Cc: linux-snps-arc@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-c6x-dev@linux-c6x.org Cc: uclinux-h8-devel@lists.sourceforge.jp Cc: linux-hexagon@vger.kernel.org Cc: linux-ia64@vger.kernel.org Cc: linux-mips@vger.kernel.org Cc: nios2-dev@lists.rocketboards.org Cc: openrisc@lists.librecores.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-riscv@lists.infradead.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: sparclinux@vger.kernel.org Cc: linux-um@lists.infradead.org Cc: linux-xtensa@linux-xtensa.org Cc: linux-arch@vger.kernel.org Acked-by: Paul Burton # MIPS parts Acked-by: Max Filippov # For xtensa changes Acked-by: Will Deacon # For the arm64 bits Reviewed-by: Thomas Gleixner # for x86 Reviewed-by: Dmitry V. Levin Reported-by: Andy Lutomirski Signed-off-by: Steven Rostedt (VMware)

Merge tag 'kvmarm-fixes-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master

2019-03-28T18:07:30Z

KVM/ARM fixes for 5.1 - Fix THP handling in the presence of pre-existing PTEs - Honor request for PTE mappings even when THPs are available - GICv4 performance improvement - Take the srcu lock when writing to guest-controlled ITS data structures - Reset the virtual PMU in preemptible context - Various cleanups

KVM: export and iif KVM is supported

2019-03-28T16:27:42Z

I do not see any consistency about headers_install of and . According to my analysis of Linux 5.1-rc1, there are 3 groups: [1] Both and are exported alpha, arm, hexagon, mips, powerpc, s390, sparc, x86 [2] is exported, but is not arc, arm64, c6x, h8300, ia64, m68k, microblaze, nios2, openrisc, parisc, sh, unicore32, xtensa [3] Neither nor is exported csky, nds32, riscv This does not match to the actual KVM support. At least, [2] is half-baked. Nor do arch maintainers look like they care about this. For example, commit 0add53713b1c ("microblaze: Add missing kvm_para.h to Kbuild") exported to user-space in order to fix an in-kernel build error. We have two ways to make this consistent: [A] export both and for all architectures, irrespective of the KVM support [B] Match the header export of and to the KVM support My first attempt was [A] because the code looks cleaner, but Paolo suggested [B]. So, this commit goes with [B]. For most architectures, was moved to the kernel-space. I changed include/uapi/linux/Kbuild so that it checks generated asm/kvm_para.h as well as check-in ones. After this commit, there will be two groups: [1] Both and are exported arm, arm64, mips, powerpc, s390, x86 [2] Neither nor is exported alpha, arc, c6x, csky, h8300, hexagon, ia64, m68k, microblaze, nds32, nios2, openrisc, parisc, riscv, sh, sparc, unicore32, xtensa Signed-off-by: Masahiro Yamada Acked-by: Cornelia Huck Signed-off-by: Paolo Bonzini

KVM: arm/arm64: Fix handling of stage2 huge mappings

2019-03-20T17:29:55Z

We rely on the mmu_notifier call backs to handle the split/merge of huge pages and thus we are guaranteed that, while creating a block mapping, either the entire block is unmapped at stage2 or it is missing permission. However, we miss a case where the block mapping is split for dirty logging case and then could later be made block mapping, if we cancel the dirty logging. This not only creates inconsistent TLB entries for the pages in the the block, but also leakes the table pages for PMD level. Handle this corner case for the huge mappings at stage2 by unmapping the non-huge mapping for the block. This could potentially release the upper level table. So we need to restart the table walk once we unmap the range. Fixes : ad361f093c1e31d ("KVM: ARM: Support hugetlbfs backed huge pages") Reported-by: Zheng Xiang Cc: Zheng Xiang Cc: Zenghui Yu Cc: Christoffer Dall Signed-off-by: Suzuki K Poulose Signed-off-by: Marc Zyngier

KVM: arm/arm64: vgic-its: Take the srcu lock when writing to guest memory

2019-03-19T17:56:56Z

When halting a guest, QEMU flushes the virtual ITS caches, which amounts to writing to the various tables that the guest has allocated. When doing this, we fail to take the srcu lock, and the kernel shouts loudly if running a lockdep kernel: [ 69.680416] ============================= [ 69.680819] WARNING: suspicious RCU usage [ 69.681526] 5.1.0-rc1-00008-g600025238f51-dirty #18 Not tainted [ 69.682096] ----------------------------- [ 69.682501] ./include/linux/kvm_host.h:605 suspicious rcu_dereference_check() usage! [ 69.683225] [ 69.683225] other info that might help us debug this: [ 69.683225] [ 69.683975] [ 69.683975] rcu_scheduler_active = 2, debug_locks = 1 [ 69.684598] 6 locks held by qemu-system-aar/4097: [ 69.685059] #0: 0000000034196013 (&kvm->lock){+.+.}, at: vgic_its_set_attr+0x244/0x3a0 [ 69.686087] #1: 00000000f2ed935e (&its->its_lock){+.+.}, at: vgic_its_set_attr+0x250/0x3a0 [ 69.686919] #2: 000000005e71ea54 (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0 [ 69.687698] #3: 00000000c17e548d (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0 [ 69.688475] #4: 00000000ba386017 (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0 [ 69.689978] #5: 00000000c2c3c335 (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0 [ 69.690729] [ 69.690729] stack backtrace: [ 69.691151] CPU: 2 PID: 4097 Comm: qemu-system-aar Not tainted 5.1.0-rc1-00008-g600025238f51-dirty #18 [ 69.691984] Hardware name: rockchip evb_rk3399/evb_rk3399, BIOS 2019.04-rc3-00124-g2feec69fb1 03/15/2019 [ 69.692831] Call trace: [ 69.694072] lockdep_rcu_suspicious+0xcc/0x110 [ 69.694490] gfn_to_memslot+0x174/0x190 [ 69.694853] kvm_write_guest+0x50/0xb0 [ 69.695209] vgic_its_save_tables_v0+0x248/0x330 [ 69.695639] vgic_its_set_attr+0x298/0x3a0 [ 69.696024] kvm_device_ioctl_attr+0x9c/0xd8 [ 69.696424] kvm_device_ioctl+0x8c/0xf8 [ 69.696788] do_vfs_ioctl+0xc8/0x960 [ 69.697128] ksys_ioctl+0x8c/0xa0 [ 69.697445] __arm64_sys_ioctl+0x28/0x38 [ 69.697817] el0_svc_common+0xd8/0x138 [ 69.698173] el0_svc_handler+0x38/0x78 [ 69.698528] el0_svc+0x8/0xc The fix is to obviously take the srcu lock, just like we do on the read side of things since bf308242ab98. One wonders why this wasn't fixed at the same time, but hey... Fixes: bf308242ab98 ("KVM: arm/arm64: VGIC/ITS: protect kvm_read_guest() calls with SRCU lock") Signed-off-by: Marc Zyngier

Merge tag 'kbuild-v5.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2019-03-17T20:25:26Z

Pull more Kbuild updates from Masahiro Yamada: - add more Build-Depends to Debian source package - prefix header search paths with $(srctree)/ - make modpost show verbose section mismatch warnings - avoid hard-coded CROSS_COMPILE for h8300 - fix regression for Debian make-kpkg command - add semantic patch to detect missing put_device() - fix some warnings of 'make deb-pkg' - optimize NOSTDINC_FLAGS evaluation - add warnings about redundant generic-y - clean up Makefiles and scripts * tag 'kbuild-v5.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kconfig: remove stale lxdialog/.gitignore kbuild: force all architectures except um to include mandatory-y kbuild: warn redundant generic-y Revert "modsign: Abort modules_install when signing fails" kbuild: Make NOSTDINC_FLAGS a simply expanded variable kbuild: deb-pkg: avoid implicit effects coccinelle: semantic code search for missing put_device() kbuild: pkg: grep include/config/auto.conf instead of $KCONFIG_CONFIG kbuild: deb-pkg: introduce is_enabled and if_enabled_echo to builddeb kbuild: deb-pkg: add CONFIG_ prefix to kernel config options kbuild: add workaround for Debian make-kpkg kbuild: source include/config/auto.conf instead of ${KCONFIG_CONFIG} unicore32: simplify linker script generation for decompressor h8300: use cc-cross-prefix instead of hardcoding h8300-unknown-linux- kbuild: move archive command to scripts/Makefile.lib modpost: always show verbose warning for section mismatch ia64: prefix header search path with $(srctree)/ libfdt: prefix header search paths with $(srctree)/ deb-pkg: generate correct build dependencies

kbuild: force all architectures except um to include mandatory-y

2019-03-17T03:56:32Z

Currently, every arch/*/include/uapi/asm/Kbuild explicitly includes the common Kbuild.asm file. Factor out the duplicated include directives to scripts/Makefile.asm-generic so that no architecture would opt out of the mandatory-y mechanism. um is not forced to include mandatory-y since it is a very exceptional case which does not support UAPI. Signed-off-by: Masahiro Yamada