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* ARM: 8809/1: proc-v7: fix Thumb annotation of cpu_v7_hvc_switch_mmArd Biesheuvel2018-11-061-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Due to what appears to be a copy/paste error, the opening ENTRY() of cpu_v7_hvc_switch_mm() lacks a matching ENDPROC(), and instead, the one for cpu_v7_smc_switch_mm() is duplicated. Given that it is ENDPROC() that emits the Thumb annotation, the cpu_v7_hvc_switch_mm() routine will be called in ARM mode on a Thumb2 kernel, resulting in the following splat: Internal error: Oops - undefined instruction: 0 [#1] SMP THUMB2 Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.18.0-rc1-00030-g4d28ad89189d-dirty #488 Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 PC is at cpu_v7_hvc_switch_mm+0x12/0x18 LR is at flush_old_exec+0x31b/0x570 pc : [<c0316efe>] lr : [<c04117c7>] psr: 00000013 sp : ee899e50 ip : 00000000 fp : 00000001 r10: eda28f34 r9 : eda31800 r8 : c12470e0 r7 : eda1fc00 r6 : eda53000 r5 : 00000000 r4 : ee88c000 r3 : c0316eec r2 : 00000001 r1 : eda53000 r0 : 6da6c000 Flags: nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Note the 'ISA ARM' in the last line. Fix this by using the correct name in ENDPROC(). Cc: <stable@vger.kernel.org> Fixes: 10115105cb3a ("ARM: spectre-v2: add firmware based hardening") Reviewed-by: Dave Martin <Dave.Martin@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
* ARM: 8797/1: spectre-v1.1: harden __copy_to_userJulien Thierry2018-10-052-2/+7
| | | | | | | | Sanitize user pointer given to __copy_to_user, both for standard version and memcopy version of the user accessor. Signed-off-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
* ARM: 8796/1: spectre-v1,v1.1: provide helpers for address sanitizationJulien Thierry2018-10-053-5/+38
| | | | | | | | | | 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>
* ARM: 8795/1: spectre-v1.1: use put_user() for __put_user()Julien Thierry2018-10-051-6/+9
| | | | | | | | | 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>
* ARM: 8794/1: uaccess: Prevent speculative use of the current addr_limitJulien Thierry2018-10-051-0/+8
| | | | | | | | | | | | | | | | 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>
* ARM: 8793/1: signal: replace __put_user_error with __put_userJulien Thierry2018-10-051-4/+4
| | | | | | | | With Spectre-v1.1 mitigations, __put_user_error is pointless. In an attempt to remove it, replace its references in frame setups with __put_user. Signed-off-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
* ARM: 8792/1: oabi-compat: copy oabi events using __copy_to_user()Julien Thierry2018-10-051-2/+6
| | | | | | | | | | Copy events to user using __copy_to_user() rather than copy members of individually with __put_user_error(). This has the benefit of disabling/enabling PAN once per event intead of once per event member. Signed-off-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
* ARM: 8791/1: vfp: use __copy_to_user() when saving VFP stateJulien Thierry2018-10-053-20/+17
| | | | | | | | | | 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>
* ARM: 8790/1: signal: always use __copy_to_user to save iwmmxt contextJulien Thierry2018-10-051-4/+6
| | | | | | | | | | When setting a dummy iwmmxt context, create a local instance and use __copy_to_user both cases whether iwmmxt is being used or not. This has the benefit of disabling/enabling PAN once for the whole copy intead of once per write. Signed-off-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
* ARM: 8789/1: signal: copy registers using __copy_to_user()Julien Thierry2018-10-051-22/+27
| | | | | | | | | | When saving the ARM integer registers, use __copy_to_user() to copy them into user signal frame, rather than __put_user_error(). This has the benefit of disabling/enabling PAN once for the whole copy intead of once per write. Signed-off-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
* ARM: spectre-v1: mitigate user accessesRussell King2018-08-022-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* ARM: spectre-v1: use get_user() for __get_user()Russell King2018-08-021-6/+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>
* ARM: use __inttype() in get_user()Russell King2018-08-021-1/+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>
* ARM: oabi-compat: copy semops using __copy_from_user()Russell King2018-08-021-3/+5
| | | | | | | | | | | | | | | | | __get_user_error() is used as a fast accessor to make copying structure members 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. Rather than using __get_user_error() to copy each semops element member, copy each semops element in full using __copy_from_user(). Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
* ARM: vfp: use __copy_from_user() when restoring VFP stateRussell King2018-08-023-24/+17
| | | | | | | | | | | | | | | | | __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>
* ARM: signal: copy registers using __copy_from_user()Russell King2018-07-261-17/+21
| | | | | | | | | | | | | | | | | __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. It becomes much more efficient to use __copy_from_user() instead, so let's use this for the ARM integer registers. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
* ARM: spectre-v1: fix syscall entryRussell King2018-06-012-11/+32
| | | | | | | | | | | Prevent speculation at the syscall table decoding by clamping the index used to zero on invalid system call numbers, and using the csdb speculative barrier. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Mark Rutland <mark.rutland@arm.com> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com>
* ARM: spectre-v1: add array_index_mask_nospec() implementationRussell King2018-06-011-0/+19
| | | | | | | | | | Add an implementation of the array_index_mask_nospec() function for mitigating Spectre variant 1 throughout the kernel. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Mark Rutland <mark.rutland@arm.com> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com>
* ARM: spectre-v1: add speculation barrier (csdb) macrosRussell King2018-06-012-0/+21
| | | | | | | | | Add assembly and C macros for the new CSDB instruction. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Mark Rutland <mark.rutland@arm.com> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com>
* ARM: KVM: report support for SMCCC_ARCH_WORKAROUND_1Russell King2018-05-311-2/+12
| | | | | | | | | | Report support for SMCCC_ARCH_WORKAROUND_1 to KVM guests for affected CPUs. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
* ARM: KVM: Add SMCCC_ARCH_WORKAROUND_1 fast handlingRussell King2018-05-311-1/+16
| | | | | | | | | | | | We want SMCCC_ARCH_WORKAROUND_1 to be fast. As fast as possible. So let's intercept it as early as we can by testing for the function call number as soon as we've identified a HVC call coming from the guest. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
* ARM: spectre-v2: KVM: invalidate icache on guest exit for Brahma B15Russell King2018-05-311-0/+1
| | | | | | | | | | Include Brahma B15 in the Spectre v2 KVM workarounds. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com>
* ARM: KVM: invalidate icache on guest exit for Cortex-A15Marc Zyngier2018-05-312-0/+29
| | | | | | | | | | | | | In order to avoid aliasing attacks against the branch predictor on Cortex-A15, let's invalidate the BTB on guest exit, which can only be done by invalidating the icache (with ACTLR[0] being set). We use the same hack as for A12/A17 to perform the vector decoding. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com>
* ARM: KVM: invalidate BTB on guest exit for Cortex-A12/A17Marc Zyngier2018-05-313-5/+85
| | | | | | | | | | | | | | | In order to avoid aliasing attacks against the branch predictor, let's invalidate the BTB on guest exit. This is made complicated by the fact that we cannot take a branch before invalidating the BTB. We only apply this to A12 and A17, which are the only two ARM cores on which this useful. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com>
* ARM: spectre-v2: warn about incorrect context switching functionsRussell King2018-05-311-0/+15
| | | | | | | | | | | Warn at error level if the context switching function is not what we are expecting. This can happen with big.Little systems, which we currently do not support. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com>
* ARM: spectre-v2: add firmware based hardeningRussell King2018-05-312-0/+81
| | | | | | | | | | Add firmware based hardening for cores that require more complex handling in firmware. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
* ARM: spectre-v2: harden user aborts in kernel spaceRussell King2018-05-315-8/+94
| | | | | | | | | | | | | | | | | In order to prevent aliasing attacks on the branch predictor, invalidate the BTB or instruction cache on CPUs that are known to be affected when taking an abort on a address that is outside of a user task limit: Cortex A8, A9, A12, A17, A73, A75: flush BTB. Cortex A15, Brahma B15: invalidate icache. If the IBE bit is not set, then there is little point to enabling the workaround. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com>
* ARM: spectre-v2: add Cortex A8 and A15 validation of the IBE bitRussell King2018-05-313-3/+39
| | | | | | | | | | | | | | When the branch predictor hardening is enabled, firmware must have set the IBE bit in the auxiliary control register. If this bit has not been set, the Spectre workarounds will not be functional. Add validation that this bit is set, and print a warning at alert level if this is not the case. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com>
* ARM: spectre-v2: harden branch predictor on context switchesRussell King2018-05-313-35/+115
| | | | | | | | | | | | | | | | | | Harden the branch predictor against Spectre v2 attacks on context switches for ARMv7 and later CPUs. We do this by: Cortex A9, A12, A17, A73, A75: invalidating the BTB. Cortex A15, Brahma B15: invalidating the instruction cache. Cortex A57 and Cortex A72 are not addressed in this patch. Cortex R7 and Cortex R8 are also not addressed as we do not enforce memory protection on these cores. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com>
* ARM: spectre: add Kconfig symbol for CPUs vulnerable to SpectreRussell King2018-05-311-0/+4
| | | | | | | | | | | Add a Kconfig symbol for CPUs which are vulnerable to the Spectre attacks. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com>
* ARM: bugs: add support for per-processor bug checkingRussell King2018-05-313-1/+10
| | | | | | | | | | | | | | | | | Add support for per-processor bug checking - each processor function descriptor gains a function pointer for this check, which must not be an __init function. If non-NULL, this will be called whenever a CPU enters the kernel via which ever path (boot CPU, secondary CPU startup, CPU resuming, etc.) This allows processor specific bug checks to validate that workaround bits are properly enabled by firmware via all entry paths to the kernel. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com>
* ARM: bugs: hook processor bug checking into SMP and suspend pathsRussell King2018-05-314-0/+13
| | | | | | | | | | | | | Check for CPU bugs when secondary processors are being brought online, and also when CPUs are resuming from a low power mode. This gives an opportunity to check that processor specific bug workarounds are correctly enabled for all paths that a CPU re-enters the kernel. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com>
* ARM: bugs: prepare processor bug infrastructureRussell King2018-05-313-2/+12
| | | | | | | | | | | Prepare the processor bug infrastructure so that it can be expanded to check for per-processor bugs. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com>
* ARM: add more CPU part numbers for Cortex and Brahma B15 CPUsRussell King2018-05-311-0/+8
| | | | | | | | | | | Add CPU part numbers for Cortex A53, A57, A72, A73, A75 and the Broadcom Brahma B15 CPU. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com>
* Linux 4.16v4.16Linus Torvalds2018-04-011-1/+1
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* Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds2018-03-312-31/+24
|\ | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "Two fixlets" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/hwbp: Simplify the perf-hwbp code, fix documentation perf/x86/intel: Fix linear IP of PEBS real_ip on Haswell and later CPUs
| * perf/hwbp: Simplify the perf-hwbp code, fix documentationLinus Torvalds2018-03-281-23/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Annoyingly, modify_user_hw_breakpoint() unnecessarily complicates the modification of a breakpoint - simplify it and remove the pointless local variables. Also update the stale Docbook while at it. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * perf/x86/intel: Fix linear IP of PEBS real_ip on Haswell and later CPUsStephane Eranian2018-03-271-8/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | this patch fix a bug in how the pebs->real_ip is handled in the PEBS handler. real_ip only exists in Haswell and later processor. It is actually the eventing IP, i.e., where the event occurred. As opposed to the pebs->ip which is the PEBS interrupt IP which is always off by one. The problem is that the real_ip just like the IP needs to be fixed up because PEBS does not record all the machine state registers, and in particular the code segement (cs). This is why we have the set_linear_ip() function. The problem was that set_linear_ip() was only used on the pebs->ip and not the pebs->real_ip. We have profiles which ran into invalid callstacks because of this. Here is an example: ..... 0: ffffffffffffff80 recent entry, marker kernel v ..... 1: 000000000040044d <= user address in kernel space! ..... 2: fffffffffffffe00 marker enter user v ..... 3: 000000000040044d ..... 4: 00000000004004b6 oldest entry Debugging output in get_perf_callchain(): [ 857.769909] CALLCHAIN: CPU8 ip=40044d regs->cs=10 user_mode(regs)=0 The problem is that the kernel entry in 1: points to a user level address. How can that be? The reason is that with PEBS sampling the instruction that caused the event to occur and the instruction where the CPU was when the interrupt was posted may be far apart. And sometime during that time window, the privilege level may change. This happens, for instance, when the PEBS sample is taken close to a kernel entry point. Here PEBS, eventing IP (real_ip) captured a user level instruction. But by the time the PMU interrupt fired, the processor had already entered kernel space. This is why the debug output shows a user address with user_mode() false. The problem comes from PEBS not recording the code segment (cs) register. The register is used in x86_64 to determine if executing in kernel vs user space. This is okay because the kernel has a software workaround called set_linear_ip(). But the issue in setup_pebs_sample_data() is that set_linear_ip() is never called on the real_ip value when it is available (Haswell and later) and precise_ip > 1. This patch fixes this problem and eliminates the callchain discrepancy. The patch restructures the code around set_linear_ip() to minimize the number of times the IP has to be set. Signed-off-by: Stephane Eranian <eranian@google.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: kan.liang@intel.com Link: http://lkml.kernel.org/r/1521788507-10231-1-git-send-email-eranian@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds2018-03-315-4/+6
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Two UV platform fixes, and a kbuild fix" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/platform/UV: Fix critical UV MMR address error x86/platform/uv/BAU: Add APIC idt entry x86/purgatory: Avoid creating stray .<pid>.d files, remove -MD from KBUILD_CFLAGS
| * | x86/platform/UV: Fix critical UV MMR address errormike.travis@hpe.com2018-03-281-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A critical error was found testing the fixed UV4 HUB in that an MMR address was found to be incorrect. This causes the virtual address space for accessing the MMIOH1 region to be allocated with the incorrect size. Fixes: 673aa20c55a1 ("x86/platform/UV: Update uv_mmrs.h to prepare for UV4A fixes") Signed-off-by: Mike Travis <travis@sgi.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Dimitri Sivanich <dimitri.sivanich@hpe.com> Cc: Russ Anderson <russ.anderson@hpe.com> Cc: Andrew Banman <andrew.banman@hpe.com> Link: https://lkml.kernel.org/r/20180328174011.041801248@stormcage.americas.sgi.com
| * | x86/platform/uv/BAU: Add APIC idt entryAndrew Banman2018-03-283-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BAU uses the old alloc_initr_gate90 method to setup its interrupt. This fails silently as the BAU vector is in the range of APIC vectors that are registered to the spurious interrupt handler. As a consequence BAU broadcasts are not handled, and the broadcast source CPU hangs. Update BAU to use new idt structure. Fixes: dc20b2d52653 ("x86/idt: Move interrupt gate initialization to IDT code") Signed-off-by: Andrew Banman <abanman@hpe.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Mike Travis <mike.travis@hpe.com> Cc: Dimitri Sivanich <sivanich@hpe.com> Cc: Russ Anderson <rja@hpe.com> Cc: stable@vger.kernel.org Cc: "H. Peter Anvin" <hpa@zytor.com> Link: https://lkml.kernel.org/r/1522188546-196177-1-git-send-email-abanman@hpe.com
| * | x86/purgatory: Avoid creating stray .<pid>.d files, remove -MD from ↵Sven Wegener2018-03-251-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | KBUILD_CFLAGS The kernel build system already takes care of generating the dependency files. Having the additional -MD in KBUILD_CFLAGS leads to stray .<pid>.d files in the build directory when we call the cc-option macro. Signed-off-by: Sven Wegener <sven.wegener@stealer.net> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthias Kaehlcke <mka@chromium.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vivek Goyal <vgoyal@redhat.com> Link: http://lkml.kernel.org/r/alpine.LNX.2.21.1803242219380.30139@titan.int.lan.stealer.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds2018-03-312-3/+12
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 PTI fixes from Ingo Molnar: "Two fixes: a relatively simple objtool fix that makes Clang built kernels work with ORC debug info, plus an alternatives macro fix" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/alternatives: Fixup alternative_call_2 objtool: Add Clang support
| * | | x86/alternatives: Fixup alternative_call_2Alexey Dobriyan2018-03-271-3/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The following pattern fails to compile while the same pattern with alternative_call() does: if (...) alternative_call_2(...); else alternative_call_2(...); as it expands into if (...) { }; <=== else { }; Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20180114120504.GA11368@avx2
| * | | objtool: Add Clang supportJosh Poimboeuf2018-03-271-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since the ORC unwinder was made the default on x86_64, Clang-built defconfig kernels have triggered some new objtool warnings: drivers/gpu/drm/i915/i915_gpu_error.o: warning: objtool: i915_error_printf()+0x6c: return with modified stack frame drivers/gpu/drm/i915/intel_display.o: warning: objtool: pipe_config_err()+0xa6: return with modified stack frame The problem is that objtool has never seen clang-built binaries before. Shockingly enough, objtool is apparently able to follow the code flow mostly fine, except for one instruction sequence. Instead of a LEAVE instruction, clang restores RSP and RBP the long way: 67c: 48 89 ec mov %rbp,%rsp 67f: 5d pop %rbp Teach objtool about this new code sequence. Reported-and-test-by: Matthias Kaehlcke <mka@chromium.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthias Kaehlcke <mka@chromium.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/fce88ce81c356eedcae7f00ed349cfaddb3363cc.1521741586.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | | Merge tag 'kbuild-fixes-v4.16-3' of ↵Linus Torvalds2018-03-315-5/+12
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild fixes from Masahiro Yamada: - fix missed rebuild of TRIM_UNUSED_KSYMS - fix rpm-pkg for GNU tar >= 1.29 - include scripts/dtc/include-prefixes/* to kernel header deb-pkg - add -no-integrated-as option ealier to fix building with Clang - fix netfilter Makefile for parallel building * tag 'kbuild-fixes-v4.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: netfilter: nf_nat_snmp_basic: add correct dependency to Makefile kbuild: rpm-pkg: Support GNU tar >= 1.29 builddeb: Fix header package regarding dtc source links kbuild: set no-integrated-as before incl. arch Makefile kbuild: make scripts/adjust_autoksyms.sh robust against timestamp races
| * | | | netfilter: nf_nat_snmp_basic: add correct dependency to MakefileMasahiro Yamada2018-03-291-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | nf_nat_snmp_basic_main.c includes a generated header, but the necessary dependency is missing in Makefile. This could cause build error in parallel building. Remove a weird line, and add a correct one. Fixes: cc2d58634e0f ("netfilter: nf_nat_snmp_basic: use asn1 decoder library") Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
| * | | | kbuild: rpm-pkg: Support GNU tar >= 1.29Jason Gunthorpe2018-03-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is a change in how command line parsing is done in this version. Excludes and includes are now ordered with the file list. Since the spec file puts the file list before the exclude list it means newer tar ignores the excludes and packs all the build output into the kernel-devel RPM resulting in a huge package. Simple argument re-ordering fixes the problem. Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
| * | | | builddeb: Fix header package regarding dtc source linksJan Kiszka2018-03-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since d5d332d3f7e8, a couple of links in scripts/dtc/include-prefixes are additionally required in order to build device trees with the header package. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Reviewed-by: Riku Voipio <riku.voipio@linaro.org> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
| * | | | kbuild: set no-integrated-as before incl. arch MakefileStefan Agner2018-03-211-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to make sure compiler flag detection for ARM works correctly the no-integrated-as flags need to be set before including the arch specific Makefile. Fixes: cfe17c9bbe6a ("kbuild: move cc-option and cc-disable-warning after incl. arch Makefile") Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
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