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2020-11-18ARM: 9019/1: kprobes: Avoid fortify_panic() when copying optprobe templateAndrew Jeffery1-11/+11
[ Upstream commit 9fa2e7af3d53a4b769136eccc32c02e128a4ee51 ] Setting both CONFIG_KPROBES=y and CONFIG_FORTIFY_SOURCE=y on ARM leads to a panic in memcpy() when injecting a kprobe despite the fixes found in commit e46daee53bb5 ("ARM: 8806/1: kprobes: Fix false positive with FORTIFY_SOURCE") and commit 0ac569bf6a79 ("ARM: 8834/1: Fix: kprobes: optimized kprobes illegal instruction"). arch/arm/include/asm/kprobes.h effectively declares the target type of the optprobe_template_entry assembly label as a u32 which leads memcpy()'s __builtin_object_size() call to determine that the pointed-to object is of size four. However, the symbol is used as a handle for the optimised probe assembly template that is at least 96 bytes in size. The symbol's use despite its type blows up the memcpy() in ARM's arch_prepare_optimized_kprobe() with a false-positive fortify_panic() when it should instead copy the optimised probe template into place: ``` $ sudo perf probe -a aspeed_g6_pinctrl_probe [ 158.457252] detected buffer overflow in memcpy [ 158.458069] ------------[ cut here ]------------ [ 158.458283] kernel BUG at lib/string.c:1153! [ 158.458436] Internal error: Oops - BUG: 0 [#1] SMP ARM [ 158.458768] Modules linked in: [ 158.459043] CPU: 1 PID: 99 Comm: perf Not tainted 5.9.0-rc7-00038-gc53ebf8167e9 #158 [ 158.459296] Hardware name: Generic DT based system [ 158.459529] PC is at fortify_panic+0x18/0x20 [ 158.459658] LR is at __irq_work_queue_local+0x3c/0x74 [ 158.459831] pc : [<8047451c>] lr : [<8020ecd4>] psr: 60000013 [ 158.460032] sp : be2d1d50 ip : be2d1c58 fp : be2d1d5c [ 158.460174] r10: 00000006 r9 : 00000000 r8 : 00000060 [ 158.460348] r7 : 8011e434 r6 : b9e0b800 r5 : 7f000000 r4 : b9fe4f0c [ 158.460557] r3 : 80c04cc8 r2 : 00000000 r1 : be7c03cc r0 : 00000022 [ 158.460801] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none [ 158.461037] Control: 10c5387d Table: b9cd806a DAC: 00000051 [ 158.461251] Process perf (pid: 99, stack limit = 0x81c71a69) [ 158.461472] Stack: (0xbe2d1d50 to 0xbe2d2000) [ 158.461757] 1d40: be2d1d84 be2d1d60 8011e724 80474510 [ 158.462104] 1d60: b9e0b800 b9fe4f0c 00000000 b9fe4f14 80c8ec80 be235000 be2d1d9c be2d1d88 [ 158.462436] 1d80: 801cee44 8011e57c b9fe4f0c 00000000 be2d1dc4 be2d1da0 801d0ad0 801cedec [ 158.462742] 1da0: 00000000 00000000 b9fe4f00 ffffffea 00000000 be235000 be2d1de4 be2d1dc8 [ 158.463087] 1dc0: 80204604 801d0738 00000000 00000000 b9fe4004 ffffffea be2d1e94 be2d1de8 [ 158.463428] 1de0: 80205434 80204570 00385c00 00000000 00000000 00000000 be2d1e14 be2d1e08 [ 158.463880] 1e00: 802ba014 b9fe4f00 b9e718c0 b9fe4f84 b9e71ec8 be2d1e24 00000000 00385c00 [ 158.464365] 1e20: 00000000 626f7270 00000065 802b905c be2d1e94 0000002e 00000000 802b9914 [ 158.464829] 1e40: be2d1e84 be2d1e50 802b9914 8028ff78 804629d0 b9e71ec0 0000002e b9e71ec0 [ 158.465141] 1e60: be2d1ea8 80c04cc8 00000cc0 b9e713c4 00000002 80205834 80205834 0000002e [ 158.465488] 1e80: be235000 be235000 be2d1ea4 be2d1e98 80205854 80204e94 be2d1ecc be2d1ea8 [ 158.465806] 1ea0: 801ee4a0 80205840 00000002 80c04cc8 00000000 0000002e 0000002e 00000000 [ 158.466110] 1ec0: be2d1f0c be2d1ed0 801ee5c8 801ee428 00000000 be2d0000 006b1fd0 00000051 [ 158.466398] 1ee0: 00000000 b9eedf00 0000002e 80204410 006b1fd0 be2d1f60 00000000 00000004 [ 158.466763] 1f00: be2d1f24 be2d1f10 8020442c 801ee4c4 80205834 802c613c be2d1f5c be2d1f28 [ 158.467102] 1f20: 802c60ac 8020441c be2d1fac be2d1f38 8010c764 802e9888 be2d1f5c b9eedf00 [ 158.467447] 1f40: b9eedf00 006b1fd0 0000002e 00000000 be2d1f94 be2d1f60 802c634c 802c5fec [ 158.467812] 1f60: 00000000 00000000 00000000 80c04cc8 006b1fd0 00000003 76f7a610 00000004 [ 158.468155] 1f80: 80100284 be2d0000 be2d1fa4 be2d1f98 802c63ec 802c62e8 00000000 be2d1fa8 [ 158.468508] 1fa0: 80100080 802c63e0 006b1fd0 00000003 00000003 006b1fd0 0000002e 00000000 [ 158.468858] 1fc0: 006b1fd0 00000003 76f7a610 00000004 006b1fb0 0026d348 00000017 7ef2738c [ 158.469202] 1fe0: 76f3431c 7ef272d8 0014ec50 76f34338 60000010 00000003 00000000 00000000 [ 158.469461] Backtrace: [ 158.469683] [<80474504>] (fortify_panic) from [<8011e724>] (arch_prepare_optimized_kprobe+0x1b4/0x1f8) [ 158.470021] [<8011e570>] (arch_prepare_optimized_kprobe) from [<801cee44>] (alloc_aggr_kprobe+0x64/0x70) [ 158.470287] r9:be235000 r8:80c8ec80 r7:b9fe4f14 r6:00000000 r5:b9fe4f0c r4:b9e0b800 [ 158.470478] [<801cede0>] (alloc_aggr_kprobe) from [<801d0ad0>] (register_kprobe+0x3a4/0x5a0) [ 158.470685] r5:00000000 r4:b9fe4f0c [ 158.470790] [<801d072c>] (register_kprobe) from [<80204604>] (__register_trace_kprobe+0xa0/0xa4) [ 158.471001] r9:be235000 r8:00000000 r7:ffffffea r6:b9fe4f00 r5:00000000 r4:00000000 [ 158.471188] [<80204564>] (__register_trace_kprobe) from [<80205434>] (trace_kprobe_create+0x5ac/0x9ac) [ 158.471408] r7:ffffffea r6:b9fe4004 r5:00000000 r4:00000000 [ 158.471553] [<80204e88>] (trace_kprobe_create) from [<80205854>] (create_or_delete_trace_kprobe+0x20/0x3c) [ 158.471766] r10:be235000 r9:be235000 r8:0000002e r7:80205834 r6:80205834 r5:00000002 [ 158.471949] r4:b9e713c4 [ 158.472027] [<80205834>] (create_or_delete_trace_kprobe) from [<801ee4a0>] (trace_run_command+0x84/0x9c) [ 158.472255] [<801ee41c>] (trace_run_command) from [<801ee5c8>] (trace_parse_run_command+0x110/0x1f8) [ 158.472471] r6:00000000 r5:0000002e r4:0000002e [ 158.472594] [<801ee4b8>] (trace_parse_run_command) from [<8020442c>] (probes_write+0x1c/0x28) [ 158.472800] r10:00000004 r9:00000000 r8:be2d1f60 r7:006b1fd0 r6:80204410 r5:0000002e [ 158.472968] r4:b9eedf00 [ 158.473046] [<80204410>] (probes_write) from [<802c60ac>] (vfs_write+0xcc/0x1e8) [ 158.473226] [<802c5fe0>] (vfs_write) from [<802c634c>] (ksys_write+0x70/0xf8) [ 158.473400] r8:00000000 r7:0000002e r6:006b1fd0 r5:b9eedf00 r4:b9eedf00 [ 158.473567] [<802c62dc>] (ksys_write) from [<802c63ec>] (sys_write+0x18/0x1c) [ 158.473745] r9:be2d0000 r8:80100284 r7:00000004 r6:76f7a610 r5:00000003 r4:006b1fd0 [ 158.473932] [<802c63d4>] (sys_write) from [<80100080>] (ret_fast_syscall+0x0/0x54) [ 158.474126] Exception stack(0xbe2d1fa8 to 0xbe2d1ff0) [ 158.474305] 1fa0: 006b1fd0 00000003 00000003 006b1fd0 0000002e 00000000 [ 158.474573] 1fc0: 006b1fd0 00000003 76f7a610 00000004 006b1fb0 0026d348 00000017 7ef2738c [ 158.474811] 1fe0: 76f3431c 7ef272d8 0014ec50 76f34338 [ 158.475171] Code: e24cb004 e1a01000 e59f0004 ebf40dd3 (e7f001f2) [ 158.475847] ---[ end trace 55a5b31c08a29f00 ]--- [ 158.476088] Kernel panic - not syncing: Fatal exception [ 158.476375] CPU0: stopping [ 158.476709] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G D 5.9.0-rc7-00038-gc53ebf8167e9 #158 [ 158.477176] Hardware name: Generic DT based system [ 158.477411] Backtrace: [ 158.477604] [<8010dd28>] (dump_backtrace) from [<8010dfd4>] (show_stack+0x20/0x24) [ 158.477990] r7:00000000 r6:60000193 r5:00000000 r4:80c2f634 [ 158.478323] [<8010dfb4>] (show_stack) from [<8046390c>] (dump_stack+0xcc/0xe8) [ 158.478686] [<80463840>] (dump_stack) from [<80110750>] (handle_IPI+0x334/0x3a0) [ 158.479063] r7:00000000 r6:00000004 r5:80b65cc8 r4:80c78278 [ 158.479352] [<8011041c>] (handle_IPI) from [<801013f8>] (gic_handle_irq+0x88/0x94) [ 158.479757] r10:10c5387d r9:80c01ed8 r8:00000000 r7:c0802000 r6:80c0537c r5:000003ff [ 158.480146] r4:c080200c r3:fffffff4 [ 158.480364] [<80101370>] (gic_handle_irq) from [<80100b6c>] (__irq_svc+0x6c/0x90) [ 158.480748] Exception stack(0x80c01ed8 to 0x80c01f20) [ 158.481031] 1ec0: 000128bc 00000000 [ 158.481499] 1ee0: be7b8174 8011d3a0 80c00000 00000000 80c04cec 80c04d28 80c5d7c2 80a026d4 [ 158.482091] 1f00: 10c5387d 80c01f34 80c01f38 80c01f28 80109554 80109558 60000013 ffffffff [ 158.482621] r9:80c00000 r8:80c5d7c2 r7:80c01f0c r6:ffffffff r5:60000013 r4:80109558 [ 158.482983] [<80109518>] (arch_cpu_idle) from [<80818780>] (default_idle_call+0x38/0x120) [ 158.483360] [<80818748>] (default_idle_call) from [<801585a8>] (do_idle+0xd4/0x158) [ 158.483945] r5:00000000 r4:80c00000 [ 158.484237] [<801584d4>] (do_idle) from [<801588f4>] (cpu_startup_entry+0x28/0x2c) [ 158.484784] r9:80c78000 r8:00000000 r7:80c78000 r6:80c78040 r5:80c04cc0 r4:000000d6 [ 158.485328] [<801588cc>] (cpu_startup_entry) from [<80810a78>] (rest_init+0x9c/0xbc) [ 158.485930] [<808109dc>] (rest_init) from [<80b00ae4>] (arch_call_rest_init+0x18/0x1c) [ 158.486503] r5:80c04cc0 r4:00000001 [ 158.486857] [<80b00acc>] (arch_call_rest_init) from [<80b00fcc>] (start_kernel+0x46c/0x548) [ 158.487589] [<80b00b60>] (start_kernel) from [<00000000>] (0x0) ``` Fixes: e46daee53bb5 ("ARM: 8806/1: kprobes: Fix false positive with FORTIFY_SOURCE") Fixes: 0ac569bf6a79 ("ARM: 8834/1: Fix: kprobes: optimized kprobes illegal instruction") Suggested-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Jeffery <andrew@aj.id.au> Tested-by: Luka Oreskovic <luka.oreskovic@sartura.hr> Tested-by: Joel Stanley <joel@jms.id.au> Reviewed-by: Joel Stanley <joel@jms.id.au> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Luka Oreskovic <luka.oreskovic@sartura.hr> Cc: Juraj Vijtiuk <juraj.vijtiuk@sartura.hr> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-01KVM: arm64: Assume write fault on S1PTW permission fault on instruction fetchMarc Zyngier1-3/+8
commit c4ad98e4b72cb5be30ea282fce935248f2300e62 upstream. KVM currently assumes that an instruction abort can never be a write. This is in general true, except when the abort is triggered by a S1PTW on instruction fetch that tries to update the S1 page tables (to set AF, for example). This can happen if the page tables have been paged out and brought back in without seeing a direct write to them (they are thus marked read only), and the fault handling code will make the PT executable(!) instead of writable. The guest gets stuck forever. In these conditions, the permission fault must be considered as a write so that the Stage-1 update can take place. This is essentially the I-side equivalent of the problem fixed by 60e21a0ef54c ("arm64: KVM: Take S1 walks into account when determining S2 write faults"). Update kvm_is_write_fault() to return true on IABT+S1PTW, and introduce kvm_vcpu_trap_is_exec_fault() that only return true when no faulting on a S1 fault. Additionally, kvm_vcpu_dabt_iss1tw() is renamed to kvm_vcpu_abt_iss1tw(), as the above makes it plain that it isn't specific to data abort. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Will Deacon <will@kernel.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200915104218.1284701-2-maz@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-26KVM: Pass MMU notifier range flags to kvm_unmap_hva_range()Will Deacon1-1/+1
commit fdfe7cbd58806522e799e2a50a15aee7f2cbb7b6 upstream. The 'flags' field of 'struct mmu_notifier_range' is used to indicate whether invalidate_range_{start,end}() are permitted to block. In the case of kvm_mmu_notifier_invalidate_range_start(), this field is not forwarded on to the architecture-specific implementation of kvm_unmap_hva_range() and therefore the backend cannot sensibly decide whether or not to block. Add an extra 'flags' parameter to kvm_unmap_hva_range() so that architectures are aware as to whether or not they are permitted to block. Cc: <stable@vger.kernel.org> Cc: Marc Zyngier <maz@kernel.org> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: James Morse <james.morse@arm.com> Signed-off-by: Will Deacon <will@kernel.org> Message-Id: <20200811102725.7121-2-will@kernel.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> [will: Backport to 4.19; use 'blockable' instead of non-existent range flags] Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-07ARM: percpu.h: fix build errorGrygorii Strashko1-0/+2
commit aa54ea903abb02303bf55855fb51e3fcee135d70 upstream. Fix build error for the case: defined(CONFIG_SMP) && !defined(CONFIG_CPU_V6) config: keystone_defconfig CC arch/arm/kernel/signal.o In file included from ../include/linux/random.h:14, from ../arch/arm/kernel/signal.c:8: ../arch/arm/include/asm/percpu.h: In function ‘__my_cpu_offset’: ../arch/arm/include/asm/percpu.h:29:34: error: ‘current_stack_pointer’ undeclared (first use in this function); did you mean ‘user_stack_pointer’? : "Q" (*(const unsigned long *)current_stack_pointer)); ^~~~~~~~~~~~~~~~~~~~~ user_stack_pointer Fixes: f227e3ec3b5c ("random32: update the net random state on interrupt and activity") Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-22KVM: arm64: Synchronize sysreg state on injecting an AArch32 exceptionMarc Zyngier1-0/+2
commit 0370964dd3ff7d3d406f292cb443a927952cbd05 upstream. On a VHE system, the EL1 state is left in the CPU most of the time, and only syncronized back to memory when vcpu_put() is called (most of the time on preemption). Which means that when injecting an exception, we'd better have a way to either: (1) write directly to the EL1 sysregs (2) synchronize the state back to memory, and do the changes there For an AArch64, we already do (1), so we are safe. Unfortunately, doing the same thing for AArch32 would be pretty invasive. Instead, we can easily implement (2) by calling the put/load architectural backends, and keep preemption disabled. We can then reload the state back into EL1. Cc: stable@vger.kernel.org Reported-by: James Morse <james.morse@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-03ARM: uaccess: fix DACR mismatch with nested exceptionsRussell King1-5/+20
[ Upstream commit 71f8af1110101facfad68989ff91f88f8e2c3e22 ] Tomas Paukrt reports that his SAM9X60 based system (ARM926, ARMv5TJ) fails to fix up alignment faults, eventually resulting in a kernel oops. The problem occurs when using CONFIG_CPU_USE_DOMAINS with commit e6978e4bf181 ("ARM: save and reset the address limit when entering an exception"). This is because the address limit is set back to TASK_SIZE on exception entry, and, although it is restored on exception exit, the domain register is not. Hence, this sequence can occur: interrupt pt_regs->addr_limit = addr_limit // USER_DS addr_limit = USER_DS alignment exception __probe_kernel_read() old_fs = get_fs() // USER_DS set_fs(KERNEL_DS) addr_limit = KERNEL_DS dacr.kernel = DOMAIN_MANAGER interrupt pt_regs->addr_limit = addr_limit // KERNEL_DS addr_limit = USER_DS alignment exception __probe_kernel_read() old_fs = get_fs() // USER_DS set_fs(KERNEL_DS) addr_limit = KERNEL_DS dacr.kernel = DOMAIN_MANAGER ... set_fs(old_fs) addr_limit = USER_DS dacr.kernel = DOMAIN_CLIENT ... addr_limit = pt_regs->addr_limit // KERNEL_DS interrupt returns At this point, addr_limit is correctly restored to KERNEL_DS for __probe_kernel_read() to continue execution, but dacr.kernel is not, it has been reset by the set_fs(old_fs) to DOMAIN_CLIENT. This would not have happened prior to the mentioned commit, because addr_limit would remain KERNEL_DS, so get_fs() would have returned KERNEL_DS, and so would correctly nest. This commit fixes the problem by also saving the DACR on exception entry if either CONFIG_CPU_SW_DOMAIN_PAN or CONFIG_CPU_USE_DOMAINS are enabled, and resetting the DACR appropriately on exception entry to match addr_limit and PAN settings. Fixes: e6978e4bf181 ("ARM: save and reset the address limit when entering an exception") Reported-by: Tomas Paukrt <tomas.paukrt@advantech.cz> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-03ARM: uaccess: integrate uaccess_save and uaccess_restoreRussell King1-17/+13
[ Upstream commit 8ede890b0bcebe8c760aacfe20e934d98c3dc6aa ] Integrate uaccess_save / uaccess_restore macros into the new uaccess_entry / uaccess_exit macros respectively. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-03ARM: uaccess: consolidate uaccess asm to asm/uaccess-asm.hRussell King2-74/+107
[ Upstream commit 747ffc2fcf969eff9309d7f2d1d61cb8b9e1bb40 ] Consolidate the user access assembly code to asm/uaccess-asm.h. This moves the csdb, check_uaccess, uaccess_mask_range_ptr, uaccess_enable, uaccess_disable, uaccess_save, uaccess_restore macros, and creates two new ones for exception entry and exit - uaccess_entry and uaccess_exit. This makes the uaccess_save and uaccess_restore macros private to asm/uaccess-asm.h. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-03ARM: 8843/1: use unified assembler in headersStefan Agner2-10/+10
[ Upstream commit c001899a5d6c2d7a0f3b75b2307ddef137fb46a6 ] Use unified assembler syntax (UAL) in headers. Divided syntax is considered deprecated. This will also allow to build the kernel using LLVM's integrated assembler. Signed-off-by: Stefan Agner <stefan@agner.ch> Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-27ARM: futex: Address build warningThomas Gleixner1-2/+7
[ Upstream commit 8101b5a1531f3390b3a69fa7934c70a8fd6566ad ] Stephen reported the following build warning on a ARM multi_v7_defconfig build with GCC 9.2.1: kernel/futex.c: In function 'do_futex': kernel/futex.c:1676:17: warning: 'oldval' may be used uninitialized in this function [-Wmaybe-uninitialized] 1676 | return oldval == cmparg; | ~~~~~~~^~~~~~~~~ kernel/futex.c:1652:6: note: 'oldval' was declared here 1652 | int oldval, ret; | ^~~~~~ introduced by commit a08971e9488d ("futex: arch_futex_atomic_op_inuser() calling conventions change"). While that change should not make any difference it confuses GCC which fails to work out that oldval is not referenced when the return value is not zero. GCC fails to properly analyze arch_futex_atomic_op_inuser(). It's not the early return, the issue is with the assembly macros. GCC fails to detect that those either set 'ret' to 0 and set oldval or set 'ret' to -EFAULT which makes oldval uninteresting. The store to the callsite supplied oldval pointer is conditional on ret == 0. The straight forward way to solve this is to make the store unconditional. Aside of addressing the build warning this makes sense anyway because it removes the conditional from the fastpath. In the error case the stored value is uninteresting and the extra store does not matter at all. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/87pncao2ph.fsf@nanos.tec.linutronix.de Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-11KVM: arm64: Only sign-extend MMIO up to register widthChristoffer Dall2-0/+7
commit b6ae256afd32f96bec0117175b329d0dd617655e upstream. On AArch64 you can do a sign-extended load to either a 32-bit or 64-bit register, and we should only sign extend the register up to the width of the register as specified in the operation (by using the 32-bit Wn or 64-bit Xn register specifier). As it turns out, the architecture provides this decoding information in the SF ("Sixty-Four" -- how cute...) bit. Let's take advantage of this with the usual 32-bit/64-bit header file dance and do the right thing on AArch64 hosts. Signed-off-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20191212195055.5541-1-christoffer.dall@arm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11KVM: arm/arm64: Correct AArch32 SPSR on exception entryMark Rutland1-0/+5
commit 1cfbb484de158e378e8971ac40f3082e53ecca55 upstream. Confusingly, there are three SPSR layouts that a kernel may need to deal with: (1) An AArch64 SPSR_ELx view of an AArch64 pstate (2) An AArch64 SPSR_ELx view of an AArch32 pstate (3) An AArch32 SPSR_* view of an AArch32 pstate When the KVM AArch32 support code deals with SPSR_{EL2,HYP}, it's either dealing with #2 or #3 consistently. On arm64 the PSR_AA32_* definitions match the AArch64 SPSR_ELx view, and on arm the PSR_AA32_* definitions match the AArch32 SPSR_* view. However, when we inject an exception into an AArch32 guest, we have to synthesize the AArch32 SPSR_* that the guest will see. Thus, an AArch64 host needs to synthesize layout #3 from layout #2. This patch adds a new host_spsr_to_spsr32() helper for this, and makes use of it in the KVM AArch32 support code. For arm64 we need to shuffle the DIT bit around, and remove the SS bit, while for arm we can use the value as-is. I've open-coded the bit manipulation for now to avoid having to rework the existing PSR_* definitions into PSR64_AA32_* and PSR32_AA32_* definitions. I hope to perform a more thorough refactoring in future so that we can handle pstate view manipulation more consistently across the kernel tree. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200108134324.46500-4-mark.rutland@arm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11KVM: arm/arm64: Correct CPSR on exception entryMark Rutland1-0/+12
commit 3c2483f15499b877ccb53250d88addb8c91da147 upstream. When KVM injects an exception into a guest, it generates the CPSR value from scratch, configuring CPSR.{M,A,I,T,E}, and setting all other bits to zero. This isn't correct, as the architecture specifies that some CPSR bits are (conditionally) cleared or set upon an exception, and others are unchanged from the original context. This patch adds logic to match the architectural behaviour. To make this simple to follow/audit/extend, documentation references are provided, and bits are configured in order of their layout in SPSR_EL2. This layout can be seen in the diagram on ARM DDI 0487E.a page C5-426. Note that this code is used by both arm and arm64, and is intended to fuction with the SPSR_EL2 and SPSR_HYP layouts. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200108134324.46500-3-mark.rutland@arm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-27ARM: 8847/1: pm: fix HYP/SVC mode mismatch when MCPM is usedMarek Szyprowski1-0/+1
[ Upstream commit ca70ea43f80c98582f5ffbbd1e6f4da2742da0c4 ] MCPM does a soft reset of the CPUs and uses common cpu_resume() routine to perform low-level platform initialization. This results in a try to install HYP stubs for the second time for each CPU and results in false HYP/SVC mode mismatch detection. The HYP stubs are already installed at the beginning of the kernel initialization on the boot CPU (head.S) or in the secondary_startup() for other CPUs. To fix this issue MCPM code should use a cpu_resume() routine without HYP stubs installation. This change fixes HYP/SVC mode mismatch on Samsung Exynos5422-based Odroid XU3/XU4/HC1 boards. Fixes: 3721924c8154 ("ARM: 8081/1: MCPM: provide infrastructure to allow for MCPM loopback") Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Nicolas Pitre <nico@linaro.org> Tested-by: Anand Moon <linux.amoon@gmail.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-13ARM: 8813/1: Make aligned 2-byte getuser()/putuser() atomic on ARMv6+Vincent Whitchurch1-0/+18
[ Upstream commit 344eb5539abf3e0b6ce22568c03e86450073e097 ] getuser() and putuser() (and there underscored variants) use two strb[t]/ldrb[t] instructions when they are asked to get/put 16-bits. This means that the read/write is not atomic even when performed to a 16-bit-aligned address. This leads to problems with vhost: vhost uses __getuser() to read the vring's 16-bit avail.index field, and if it happens to observe a partial update of the index, wrong descriptors will be used which will lead to a breakdown of the virtio communication. A similar problem exists for __putuser() which is used to write to the vring's used.index field. The reason these functions use strb[t]/ldrb[t] is because strht/ldrht instructions did not exist until ARMv6T2/ARMv7. So we should be easily able to fix this on ARMv7. Also, since all ARMv6 processors also don't actually use the unprivileged instructions anymore for uaccess (since CONFIG_CPU_USE_DOMAINS is not used) we can easily fix them too. Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-06-15ARM: prevent tracing IPI_CPU_BACKTRACEArnd Bergmann1-0/+1
[ 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 <arnd@arndb.de> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Mathieu Malaterre <malat@debian.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Stefan Agner <stefan@agner.ch> Cc: Boris Brezillon <bbrezillon@kernel.org> Cc: Miquel Raynal <miquel.raynal@bootlin.com> Cc: Richard Weinberger <richard@nod.at> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Brian Norris <computersforpeace@gmail.com> Cc: Marek Vasut <marek.vasut@gmail.com> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Borislav Petkov <bp@suse.de> Cc: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31ARM: vdso: Remove dependency with the arch_timer driver internalsMarc Zyngier1-0/+2
[ 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 <mark.rutland@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-04KVM: arm/arm64: vgic-its: Take the srcu lock when writing to guest memoryMarc Zyngier1-0/+11
[ Upstream commit a6ecfb11bf37743c1ac49b266595582b107b61d4 ] 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 <marc.zyngier@arm.com> Signed-off-by: Sasha Levin (Microsoft) <sashal@kernel.org>
2019-04-05ARM: avoid Cortex-A9 livelock on tight dmb loopsRussell King2-1/+7
[ Upstream commit 5388a5b82199facacd3d7ac0d05aca6e8f902fed ] machine_crash_nonpanic_core() does this: while (1) cpu_relax(); because the kernel has crashed, and we have no known safe way to deal with the CPU. So, we place the CPU into an infinite loop which we expect it to never exit - at least not until the system as a whole is reset by some method. In the absence of erratum 754327, this code assembles to: b . In other words, an infinite loop. When erratum 754327 is enabled, this becomes: 1: dmb b 1b It has been observed that on some systems (eg, OMAP4) where, if a crash is triggered, the system tries to kexec into the panic kernel, but fails after taking the secondary CPU down - placing it into one of these loops. This causes the system to livelock, and the most noticable effect is the system stops after issuing: Loading crashdump kernel... to the system console. The tested as working solution I came up with was to add wfe() to these infinite loops thusly: while (1) { cpu_relax(); wfe(); } which, without 754327 builds to: 1: wfe b 1b or with 754327 is enabled: 1: dmb wfe b 1b Adding "wfe" does two things depending on the environment we're running under: - where we're running on bare metal, and the processor implements "wfe", it stops us spinning endlessly in a loop where we're never going to do any useful work. - if we're running in a VM, it allows the CPU to be given back to the hypervisor and rescheduled for other purposes (maybe a different VM) rather than wasting CPU cycles inside a crashed VM. However, in light of erratum 794072, Will Deacon wanted to see 10 nops as well - which is reasonable to cover the case where we have erratum 754327 enabled _and_ we have a processor that doesn't implement the wfe hint. So, we now end up with: 1: wfe b 1b when erratum 754327 is disabled, or: 1: dmb nop nop nop nop nop nop nop nop nop nop wfe b 1b when erratum 754327 is enabled. We also get the dmb + 10 nop sequence elsewhere in the kernel, in terminating loops. This is reasonable - it means we get the workaround for erratum 794072 when erratum 754327 is enabled, but still relinquish the dead processor - either by placing it in a lower power mode when wfe is implemented as such or by returning it to the hypervisior, or in the case where wfe is a no-op, we use the workaround specified in erratum 794072 to avoid the problem. These as two entirely orthogonal problems - the 10 nops addresses erratum 794072, and the wfe is an optimisation that makes the system more efficient when crashed either in terms of power consumption or by allowing the host/other VMs to make use of the CPU. I don't see any reason not to use kexec() inside a VM - it has the potential to provide automated recovery from a failure of the VMs kernel with the opportunity for saving a crashdump of the failure. A panic() with a reboot timeout won't do that, and reading the libvirt documentation, setting on_reboot to "preserve" won't either (the documentation states "The preserve action for an on_reboot event is treated as a destroy".) Surely it has to be a good thing to avoiding having CPUs spinning inside a VM that is doing no useful work. Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-05ARM: 8830/1: NOMMU: Toggle only bits in EXC_RETURN we are really care ofVladimir Murzin1-1/+1
[ Upstream commit 72cd4064fccaae15ab84d40d4be23667402df4ed ] ARMv8M introduces support for Security extension to M class, among other things it affects exception handling, especially, encoding of EXC_RETURN. The new bits have been added: Bit [6] Secure or Non-secure stack Bit [5] Default callee register stacking Bit [0] Exception Secure which conflicts with hard-coded value of EXC_RETURN: In fact, we only care of few bits: Bit [3] Mode (0 - Handler, 1 - Thread) Bit [2] Stack pointer selection (0 - Main, 1 - Process) We can toggle only those bits and left other bits as they were on exception entry. It is basically, what patch does - saves EXC_RETURN when we do transition form Thread to Handler mode (it is first svc), so later saved value is used instead of EXC_RET_THREADMODE_PROCESSSTACK. Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-23ARM: 8824/1: fix a migrating irq bug when hotplug cpuDietmar Eggemann1-1/+0
[ Upstream commit 1b5ba350784242eb1f899bcffd95d2c7cff61e84 ] Arm TC2 fails cpu hotplug stress test. This issue was tracked down to a missing copy of the new affinity cpumask for the vexpress-spc interrupt into struct irq_common_data.affinity when the interrupt is migrated in migrate_one_irq(). Fix it by replacing the arm specific hotplug cpu migration with the generic irq code. This is the counterpart implementation to commit 217d453d473c ("arm64: fix a migrating irq bug when hotplug cpu"). Tested with cpu hotplug stress test on Arm TC2 (multi_v7_defconfig plus CONFIG_ARM_BIG_LITTLE_CPUFREQ=y and CONFIG_ARM_VEXPRESS_SPC_CPUFREQ=y). The vexpress-spc interrupt (irq=22) on this board is affine to CPU0. Its affinity cpumask now changes correctly e.g. from 0 to 1-4 when CPU0 is hotplugged out. Suggested-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-23arm/arm64: KVM: Allow a VCPU to fully reset itselfMarc Zyngier1-0/+10
[ Upstream commit 358b28f09f0ab074d781df72b8a671edb1547789 ] The current kvm_psci_vcpu_on implementation will directly try to manipulate the state of the VCPU to reset it. However, since this is not done on the thread that runs the VCPU, we can end up in a strangely corrupted state when the source and target VCPUs are running at the same time. Fix this by factoring out all reset logic from the PSCI implementation and forwarding the required information along with a request to the target VCPU. Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-20ARM: spectre-v2: per-CPU vtables to work around big.Little systemsRussell King1-0/+23
Commit 383fb3ee8024d596f488d2dbaf45e572897acbdb upstream. In big.Little systems, some CPUs require the Spectre workarounds in paths such as the context switch, but other CPUs do not. In order to handle these differences, we need per-CPU vtables. We are unable to use the kernel's per-CPU variables to support this as per-CPU is not initialised at times when we need access to the vtables, so we have to use an array indexed by logical CPU number. We use an array-of-pointers to avoid having function pointers in the kernel's read/write .data section. Reviewed-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: David A. Long <dave.long@linaro.org> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-20ARM: add PROC_VTABLE and PROC_TABLE macrosRussell King1-13/+26
Commit e209950fdd065d2cc46e6338e47e52841b830cba upstream. Allow the way we access members of the processor vtable to be changed at compile time. We will need to move to per-CPU vtables to fix the Spectre variant 2 issues on big.Little systems. However, we have a couple of calls that do not need the vtable treatment, and indeed cause a kernel warning due to the (later) use of smp_processor_id(), so also introduce the PROC_TABLE macro for these which always use CPU 0's function pointers. Reviewed-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: David A. Long <dave.long@linaro.org> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-20ARM: clean up per-processor check_bugs method callRussell King1-0/+1
Commit 945aceb1db8885d3a35790cf2e810f681db52756 upstream. Call the per-processor type check_bugs() method in the same way as we do other per-processor functions - move the "processor." detail into proc-fns.h. Reviewed-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: David A. Long <dave.long@linaro.org> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-20ARM: split out processor lookupRussell King1-0/+1
Commit 65987a8553061515b5851b472081aedb9837a391 upstream. Split out the lookup of the processor type and associated error handling from the rest of setup_processor() - we will need to use this in the secondary CPU bringup path for big.Little Spectre variant 2 mitigation. Reviewed-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: David A. Long <dave.long@linaro.org> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Tested-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-20ARM: 8796/1: spectre-v1,v1.1: provide helpers for address sanitizationJulien Thierry2-0/+37
Commit afaf6838f4bc896a711180b702b388b8cfa638fc upstream. Introduce C and asm helpers to sanitize user address, taking the address range they target into account. Use asm helper for existing sanitization in __copy_from_user(). Signed-off-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: David A. Long <dave.long@linaro.org> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-20ARM: 8795/1: spectre-v1.1: use put_user() for __put_user()Julien Thierry1-6/+9
Commit e3aa6243434fd9a82e84bb79ab1abd14f2d9a5a7 upstream. When Spectre mitigation is required, __put_user() needs to include check_uaccess. This is already the case for put_user(), so just make __put_user() an alias of put_user(). Signed-off-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: David A. Long <dave.long@linaro.org> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-20ARM: 8794/1: uaccess: Prevent speculative use of the current addr_limitJulien Thierry1-0/+8
Commit 621afc677465db231662ed126ae1f355bf8eac47 upstream. A mispredicted conditional call to set_fs could result in the wrong addr_limit being forwarded under speculation to a subsequent access_ok check, potentially forming part of a spectre-v1 attack using uaccess routines. This patch prevents this forwarding from taking place, but putting heavy barriers in set_fs after writing the addr_limit. Porting commit c2f0ad4fc089cff8 ("arm64: uaccess: Prevent speculative use of the current addr_limit"). Signed-off-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: David A. Long <dave.long@linaro.org> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-20ARM: 8791/1: vfp: use __copy_to_user() when saving VFP stateJulien Thierry1-2/+2
Commit 3aa2df6ec2ca6bc143a65351cca4266d03a8bc41 upstream. Use __copy_to_user() rather than __put_user_error() for individual members when saving VFP state. This has the benefit of disabling/enabling PAN once per copied struct intead of once per write. Signed-off-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: David A. Long <dave.long@linaro.org> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-12-29mm: make the __PAGETABLE_PxD_FOLDED defines non-emptyMartin Schwidefsky1-1/+1
[ Upstream commit a8874e7e8a8896f2b6c641f4b8e2473eafd35204 ] Change the currently empty defines for __PAGETABLE_PMD_FOLDED, __PAGETABLE_PUD_FOLDED and __PAGETABLE_P4D_FOLDED to return 1. This makes it possible to use __is_defined() to test if the preprocessor define exists. Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-09-07KVM: Remove obsolete kvm_unmap_hva notifier backendMarc Zyngier1-1/+0
kvm_unmap_hva is long gone, and we only have kvm_unmap_hva_range to deal with. Drop the now obsolete code. Fixes: fb1522e099f0 ("KVM: update to new mmu_notifier semantic v2") Cc: James Hogan <jhogan@kernel.org> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
2018-08-22Merge tag 'kvmarm-for-v4.19' of ↵Paolo Bonzini3-12/+19
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm updates for 4.19 - Support for Group0 interrupts in guests - Cache management optimizations for ARMv8.4 systems - Userspace interface for RAS, allowing error retrival and injection - Fault path optimization - Emulated physical timer fixes - Random cleanups
2018-08-17Merge tag 'modules-for-v4.19' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux Pull modules updates from Jessica Yu: "Summary of modules changes for the 4.19 merge window: - Fix modules kallsyms for livepatch. Livepatch modules can have SHN_UNDEF symbols in their module symbol tables for later symbol resolution, but kallsyms shouldn't be returning these symbols - Some code cleanups and minor reshuffling in load_module() were done to log the module name when module signature verification fails" * tag 'modules-for-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: kernel/module: Use kmemdup to replace kmalloc+memcpy ARM: module: fix modsign build error modsign: log module name in the event of an error module: replace VMLINUX_SYMBOL_STR() with __stringify() or string literal module: print sensible error code module: setup load info before module_sig_check() module: make it clear when we're handling the module copy in info->hdr module: exclude SHN_UNDEF symbols from kallsyms api
2018-08-15Merge tag 'arm64-upstream' of ↵Linus Torvalds1-7/+7
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "A bunch of good stuff in here. Worth noting is that we've pulled in the x86/mm branch from -tip so that we can make use of the core ioremap changes which allow us to put down huge mappings in the vmalloc area without screwing up the TLB. Much of the positive diffstat is because of the rseq selftest for arm64. Summary: - Wire up support for qspinlock, replacing our trusty ticket lock code - Add an IPI to flush_icache_range() to ensure that stale instructions fetched into the pipeline are discarded along with the I-cache lines - Support for the GCC "stackleak" plugin - Support for restartable sequences, plus an arm64 port for the selftest - Kexec/kdump support on systems booting with ACPI - Rewrite of our syscall entry code in C, which allows us to zero the GPRs on entry from userspace - Support for chained PMU counters, allowing 64-bit event counters to be constructed on current CPUs - Ensure scheduler topology information is kept up-to-date with CPU hotplug events - Re-enable support for huge vmalloc/IO mappings now that the core code has the correct hooks to use break-before-make sequences - Miscellaneous, non-critical fixes and cleanups" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (90 commits) arm64: alternative: Use true and false for boolean values arm64: kexec: Add comment to explain use of __flush_icache_range() arm64: sdei: Mark sdei stack helper functions as static arm64, kaslr: export offset in VMCOREINFO ELF notes arm64: perf: Add cap_user_time aarch64 efi/libstub: Only disable stackleak plugin for arm64 arm64: drop unused kernel_neon_begin_partial() macro arm64: kexec: machine_kexec should call __flush_icache_range arm64: svc: Ensure hardirq tracing is updated before return arm64: mm: Export __sync_icache_dcache() for xen-privcmd drivers/perf: arm-ccn: Use devm_ioremap_resource() to map memory arm64: Add support for STACKLEAK gcc plugin arm64: Add stack information to on_accessible_stack drivers/perf: hisi: update the sccl_id/ccl_id when MT is supported arm64: fix ACPI dependencies rseq/selftests: Add support for arm64 arm64: acpi: fix alignment fault in accessing ACPI efi/arm: map UEFI memory map even w/o runtime services enabled efi/arm: preserve early mapping of UEFI memory map longer for BGRT drivers: acpi: add dependency of EFI for arm64 ...
2018-08-14Merge branch 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-armLinus Torvalds4-92/+34
Pull ARM updates from Russell King: - further Spectre variant 1 fixes for user accessors. - kbuild cleanups (Masahiro Yamada) - hook up sync core functionality (Will Deacon) - nommu updates for hypervisor mode booting (Vladimir Murzin) - use compiler built-ins for fls and ffs (Nicolas Pitre) * 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: ARM: spectre-v1: mitigate user accesses ARM: spectre-v1: use get_user() for __get_user() ARM: use __inttype() in get_user() ARM: oabi-compat: copy semops using __copy_from_user() ARM: vfp: use __copy_from_user() when restoring VFP state ARM: 8785/1: use compiler built-ins for ffs and fls ARM: 8784/1: NOMMU: Allow enter in Hyp mode ARM: 8783/1: NOMMU: Extend check for VBAR support ARM: 8782/1: vfp: clean up arch/arm/vfp/Makefile ARM: signal: copy registers using __copy_from_user() ARM: tcm: ensure inline stub functions are marked static ARM: 8779/1: add endianness option to LDFLAGS instead of LD ARM: 8777/1: Hook up SYNC_CORE functionality for sys_membarrier()
2018-08-14Merge branch 'x86-timers-for-linus' of ↵Linus Torvalds1-2/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 timer updates from Thomas Gleixner: "Early TSC based time stamping to allow better boot time analysis. This comes with a general cleanup of the TSC calibration code which grew warts and duct taping over the years and removes 250 lines of code. Initiated and mostly implemented by Pavel with help from various folks" * 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits) x86/kvmclock: Mark kvm_get_preset_lpj() as __init x86/tsc: Consolidate init code sched/clock: Disable interrupts when calling generic_sched_clock_init() timekeeping: Prevent false warning when persistent clock is not available sched/clock: Close a hole in sched_clock_init() x86/tsc: Make use of tsc_calibrate_cpu_early() x86/tsc: Split native_calibrate_cpu() into early and late parts sched/clock: Use static key for sched_clock_running sched/clock: Enable sched clock early sched/clock: Move sched clock initialization and merge with generic clock x86/tsc: Use TSC as sched clock early x86/tsc: Initialize cyc2ns when tsc frequency is determined x86/tsc: Calibrate tsc only once ARM/time: Remove read_boot_clock64() s390/time: Remove read_boot_clock64() timekeeping: Default boot time offset to local_clock() timekeeping: Replace read_boot_clock64() with read_persistent_wall_and_boot_offset() s390/time: Add read_persistent_wall_and_boot_offset() x86/xen/time: Output xen sched_clock time from 0 x86/xen/time: Initialize pv xen time in init_hypervisor_platform() ...
2018-08-14Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds1-0/+8
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mm updates from Thomas Gleixner: - Make lazy TLB mode even lazier to avoid pointless switch_mm() operations, which reduces CPU load by 1-2% for memcache workloads - Small cleanups and improvements all over the place * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Remove redundant check for kmem_cache_create() arm/asm/tlb.h: Fix build error implicit func declaration x86/mm/tlb: Make clear_asid_other() static x86/mm/tlb: Skip atomic operations for 'init_mm' in switch_mm_irqs_off() x86/mm/tlb: Always use lazy TLB mode x86/mm/tlb: Only send page table free TLB flush to lazy TLB CPUs x86/mm/tlb: Make lazy TLB mode lazier x86/mm/tlb: Restructure switch_mm_irqs_off() x86/mm/tlb: Leave lazy TLB mode at page table free time mm: Allocate the mm_cpumask (mm->cpu_bitmap[]) dynamically based on nr_cpu_ids x86/mm: Add TLB purge to free pmd/pte page interfaces ioremap: Update pgtable free interfaces with addr x86/mm: Disable ioremap free page handling on x86-PAE
2018-08-13Merge branch 'perf-core-for-linus' of ↵Linus Torvalds3-5/+5
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf update from Thomas Gleixner: "The perf crowd presents: Kernel updates: - Removal of jprobes - Cleanup and consolidatation the handling of kprobes - Cleanup and consolidation of hardware breakpoints - The usual pile of fixes and updates to PMUs and event descriptors Tooling updates: - Updates and improvements all over the place. Nothing outstanding, just the (good) boring incremental grump work" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (103 commits) perf trace: Do not require --no-syscalls to suppress strace like output perf bpf: Include uapi/linux/bpf.h from the 'perf trace' script's bpf.h perf tools: Allow overriding MAX_NR_CPUS at compile time perf bpf: Show better message when failing to load an object perf list: Unify metric group description format with PMU event description perf vendor events arm64: Update ThunderX2 implementation defined pmu core events perf cs-etm: Generate branch sample for CS_ETM_TRACE_ON packet perf cs-etm: Generate branch sample when receiving a CS_ETM_TRACE_ON packet perf cs-etm: Support dummy address value for CS_ETM_TRACE_ON packet perf cs-etm: Fix start tracing packet handling perf build: Fix installation directory for eBPF perf c2c report: Fix crash for empty browser perf tests: Fix indexing when invoking subtests perf trace: Beautify the AF_INET & AF_INET6 'socket' syscall 'protocol' args perf trace beauty: Add beautifiers for 'socket''s 'protocol' arg perf trace beauty: Do not print NULL strarray entries perf beauty: Add a generator for IPPROTO_ socket's protocol constants tools include uapi: Grab a copy of linux/in.h perf tests: Fix complex event name parsing perf evlist: Fix error out while applying initial delay and LBR ...
2018-08-13Merge branch 'locking-core-for-linus' of ↵Linus Torvalds1-41/+14
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking/atomics update from Thomas Gleixner: "The locking, atomics and memory model brains delivered: - A larger update to the atomics code which reworks the ordering barriers, consolidates the atomic primitives, provides the new atomic64_fetch_add_unless() primitive and cleans up the include hell. - Simplify cmpxchg() instrumentation and add instrumentation for xchg() and cmpxchg_double(). - Updates to the memory model and documentation" * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (48 commits) locking/atomics: Rework ordering barriers locking/atomics: Instrument cmpxchg_double*() locking/atomics: Instrument xchg() locking/atomics: Simplify cmpxchg() instrumentation locking/atomics/x86: Reduce arch_cmpxchg64*() instrumentation tools/memory-model: Rename litmus tests to comply to norm7 tools/memory-model/Documentation: Fix typo, smb->smp sched/Documentation: Update wake_up() & co. memory-barrier guarantees locking/spinlock, sched/core: Clarify requirements for smp_mb__after_spinlock() sched/core: Use smp_mb() in wake_woken_function() tools/memory-model: Add informal LKMM documentation to MAINTAINERS locking/atomics/Documentation: Describe atomic_set() as a write operation tools/memory-model: Make scripts executable tools/memory-model: Remove ACCESS_ONCE() from model tools/memory-model: Remove ACCESS_ONCE() from recipes locking/memory-barriers.txt/kokr: Update Korean translation to fix broken DMA vs. MMIO ordering example MAINTAINERS: Add Daniel Lustig as an LKMM reviewer tools/memory-model: Fix ISA2+pooncelock+pooncelock+pombonce name tools/memory-model: Add litmus test for full multicopy atomicity locking/refcount: Always allow checked forms ...
2018-08-13Merge branch 'irq-core-for-linus' of ↵Linus Torvalds2-6/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull genirq updates from Thomas Gleixner: "The irq departement provides: - A synchronization fix for free_irq() to synchronize just the removed interrupt thread on shared interrupt lines. - Consolidate the multi low level interrupt entry handling and mvoe it to the generic code instead of adding yet another copy for RISC-V - Refactoring of the ARM LPI allocator and LPI exposure to the hypervisor - Yet another interrupt chip driver for the JZ4725B SoC - Speed up for /proc/interrupts as people seem to love reading this file with high frequency - Miscellaneous fixes and updates" * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) irqchip/gic-v3-its: Make its_lock a raw_spin_lock_t genirq/irqchip: Remove MULTI_IRQ_HANDLER as it's now obselete openrisc: Use the new GENERIC_IRQ_MULTI_HANDLER arm64: Use the new GENERIC_IRQ_MULTI_HANDLER ARM: Convert to GENERIC_IRQ_MULTI_HANDLER irqchip: Port the ARM IRQ drivers to GENERIC_IRQ_MULTI_HANDLER irqchip/gic-v3-its: Reduce minimum LPI allocation to 1 for PCI devices dt-bindings: irqchip: renesas-irqc: Document r8a77980 support dt-bindings: irqchip: renesas-irqc: Document r8a77470 support irqchip/ingenic: Add support for the JZ4725B SoC irqchip/stm32: Add exti0 translation for stm32mp1 genirq: Remove redundant NULL pointer check in __free_irq() irqchip/gic-v3-its: Honor hypervisor enforced LPI range irqchip/gic-v3: Expose GICD_TYPER in the rdist structure irqchip/gic-v3-its: Drop chunk allocation compatibility irqchip/gic-v3-its: Move minimum LPI requirements to individual busses irqchip/gic-v3-its: Use full range of LPIs irqchip/gic-v3-its: Refactor LPI allocator genirq: Synchronize only with single thread on free_irq() genirq: Update code comments wrt recycled thread_mask ...
2018-08-13Merge branches 'fixes', 'misc' and 'spectre' into for-linusRussell King4-92/+34
Conflicts: arch/arm/include/asm/uaccess.h Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-08-12KVM: arm: Use true and false for boolean valuesGustavo A. R. Silva1-1/+1
Return statements in functions returning bool should use true or false instead of an integer value. This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-08-03ARM: Convert to GENERIC_IRQ_MULTI_HANDLERPalmer Dabbelt2-6/+1
Converts the ARM interrupt code to use the recently added GENERIC_IRQ_MULTI_HANDLER, which is essentially just a copy of ARM's existhing MULTI_IRQ_HANDLER. The only changes are: * handle_arch_irq is now defined in a generic C file instead of an arm-specific assembly file. * handle_arch_irq is now marked as __ro_after_init. Signed-off-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux@armlinux.org.uk Cc: catalin.marinas@arm.com Cc: Will Deacon <will.deacon@arm.com> Cc: jonas@southpole.se Cc: stefan.kristiansson@saunalahti.fi Cc: shorne@gmail.com Cc: jason@lakedaemon.net Cc: marc.zyngier@arm.com Cc: Arnd Bergmann <arnd@arndb.de> Cc: nicolas.pitre@linaro.org Cc: vladimir.murzin@arm.com Cc: keescook@chromium.org Cc: jinb.park7@gmail.com Cc: yamada.masahiro@socionext.com Cc: alexandre.belloni@bootlin.com Cc: pombredanne@nexb.com Cc: Greg KH <gregkh@linuxfoundation.org> Cc: kstewart@linuxfoundation.org Cc: jhogan@kernel.org Cc: mark.rutland@arm.com Cc: ard.biesheuvel@linaro.org Cc: james.morse@arm.com Cc: linux-arm-kernel@lists.infradead.org Cc: openrisc@lists.librecores.org Link: https://lkml.kernel.org/r/20180622170126.6308-3-palmer@sifive.com
2018-08-02ARM: spectre-v1: mitigate user accessesRussell King1-0/+4
Spectre variant 1 attacks are about this sequence of pseudo-code: index = load(user-manipulated pointer); access(base + index * stride); In order for the cache side-channel to work, the access() must me made to memory which userspace can detect whether cache lines have been loaded. On 32-bit ARM, this must be either user accessible memory, or a kernel mapping of that same user accessible memory. The problem occurs when the load() speculatively loads privileged data, and the subsequent access() is made to user accessible memory. Any load() which makes use of a user-maniplated pointer is a potential problem if the data it has loaded is used in a subsequent access. This also applies for the access() if the data loaded by that access is used by a subsequent access. Harden the get_user() accessors against Spectre attacks by forcing out of bounds addresses to a NULL pointer. This prevents get_user() being used as the load() step above. As a side effect, put_user() will also be affected even though it isn't implicated. Also harden copy_from_user() by redoing the bounds check within the arm_copy_from_user() code, and NULLing the pointer if out of bounds. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-08-02ARM: spectre-v1: use get_user() for __get_user()Russell King1-6/+11
Fixing __get_user() for spectre variant 1 is not sane: we would have to add address space bounds checking in order to validate that the location should be accessed, and then zero the address if found to be invalid. Since __get_user() is supposed to avoid the bounds check, and this is exactly what get_user() does, there's no point having two different implementations that are doing the same thing. So, when the Spectre workarounds are required, make __get_user() an alias of get_user(). Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-08-02ARM: use __inttype() in get_user()Russell King1-1/+8
Borrow the x86 implementation of __inttype() to use in get_user() to select an integer type suitable to temporarily hold the result value. This is necessary to avoid propagating the volatile nature of the result argument, which can cause the following warning: lib/iov_iter.c:413:5: warning: optimization may eliminate reads and/or writes to register variables [-Wvolatile-register-var] Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-08-02ARM: vfp: use __copy_from_user() when restoring VFP stateRussell King1-2/+2
__get_user_error() is used as a fast accessor to make copying structure members in the signal handling path as efficient as possible. However, with software PAN and the recent Spectre variant 1, the efficiency is reduced as these are no longer fast accessors. In the case of software PAN, it has to switch the domain register around each access, and with Spectre variant 1, it would have to repeat the access_ok() check for each access. Use __copy_from_user() rather than __get_user_err() for individual members when restoring VFP state. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-07-30ARM: 8785/1: use compiler built-ins for ffs and flsNicolas Pitre1-83/+9
On ARMv5 and above, it is beneficial to use compiler built-ins such as __builtin_ffs() and __builtin_ctzl() to implement ffs(), __ffs(), fls() and __fls(). The compiler does inline the clz instruction and even the rbit instruction when available, or provide a constant value when possible. On ARMv4 the compiler calls out to helper functions for those built-ins so it is best to keep the open coded versions in that case. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-07-25arm/asm/tlb.h: Fix build error implicit func declarationAnders Roxell1-0/+8
Building on arm 32 with LPAE enabled we don't include asm-generic/tlb.h, where we have tlb_flush_remove_tables_local and tlb_flush_remove_tables defined. The build fails with: mm/memory.c: In function ‘tlb_remove_table_smp_sync’: mm/memory.c:339:2: error: implicit declaration of function ‘tlb_flush_remove_tables_local’; did you mean ‘tlb_remove_table’? [-Werror=implicit-function-declaration] ... This bug got introduced in: 2ff6ddf19c0e ("x86/mm/tlb: Leave lazy TLB mode at page table free time") To fix this issue we define them in arm 32's specific asm/tlb.h file as well. Signed-off-by: Anders Roxell <anders.roxell@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dave.hansen@intel.com Cc: linux-arm-kernel@lists.infradead.org Cc: linux@armlinux.org.uk Cc: riel@surriel.com Cc: songliubraving@fb.com Fixes: 2ff6ddf19c0e ("x86/mm/tlb: Leave lazy TLB mode at page table free time") Link: http://lkml.kernel.org/r/20180725095557.19668-1-anders.roxell@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>