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2017-04-20powerpc/kprobes: Fix handling of function offsets on ABIv2Naveen N. Rao
commit 239aeba76409 ("perf powerpc: Fix kprobe and kretprobe handling with kallsyms on ppc64le") changed how we use the offset field in struct kprobe on ABIv2. perf now offsets from the global entry point if an offset is specified and otherwise chooses the local entry point. Fix the same in kernel for kprobe API users. We do this by extending kprobe_lookup_name() to accept an additional parameter to indicate the offset specified with the kprobe registration. If offset is 0, we return the local function entry and return the global entry point otherwise. With: # cd /sys/kernel/debug/tracing/ # echo "p _do_fork" >> kprobe_events # echo "p _do_fork+0x10" >> kprobe_events before this patch: # cat ../kprobes/list c0000000000d0748 k _do_fork+0x8 [DISABLED] c0000000000d0758 k _do_fork+0x18 [DISABLED] c0000000000412b0 k kretprobe_trampoline+0x0 [OPTIMIZED] and after: # cat ../kprobes/list c0000000000d04c8 k _do_fork+0x8 [DISABLED] c0000000000d04d0 k _do_fork+0x10 [DISABLED] c0000000000412b0 k kretprobe_trampoline+0x0 [OPTIMIZED] Acked-by: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-20kprobes: Convert kprobe_lookup_name() to a functionNaveen N. Rao
The macro is now pretty long and ugly on powerpc. In the light of further changes needed here, convert it to a __weak variant to be over-ridden with a nicer looking function. Suggested-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-20KVM: PPC: iommu: Unify TCE checkingAlexey Kardashevskiy
This reworks helpers for checking TCE update parameters in way they can be used in KVM. This should cause no behavioral change. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-04-19powerpc/powernv: Override pcibios_default_alignment() to force PCI devices ↵Yongji Xie
to be page aligned Override pcibios_default_alignment() to set default alignment to PAGE_SIZE for all PCI devices on PowerNV platform. Thus sub-page BARs would not share a page and could be mapped into guest when VFIO passthrough them. Signed-off-by: Yongji Xie <elohimes@gmail.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2017-04-19powerpc/64s: Minor fix for MCE TLB flush for radixNicholas Piggin
The TLB flush for radix first flushes TLB for radix configuration, then flushes for hash configuration. The second flush is unnecessary but does not affect correctness. Fixes: 1a472c9dba6b9 ("powerpc/mm/radix: Add tlbflush routines") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-19powerpc/64s: Revert setting of LPCR[LPES] on POWER9Nicholas Piggin
The XIVE enablement patches included a change to set the LPES (Logical Partitioning Environment Selector) bit (bit # 3) in LPCR (Logical Partitioning Control Register) on POWER9 hosts. This bit sets external interrupts to guest delivery mode, which uses SRR0/1. The host's EE interrupt handler is written to expect HSRR0/1 (for earlier CPUs). This should be fine because XIVE is configured not to deliver EEs to the host (Hypervisor Virtulization Interrupt is used instead) so the EE handler should never be executed. However a bug in interrupt controller code, hardware, or odd configuration of a simulator could result in the host getting an EE incorrectly. Keeping the EE delivery mode matching the host EE handler prevents strange crashes due to using the wrong exception registers. KVM will configure the LPCR to set LPES prior to running a guest so that EEs are delivered to the guest using SRR0/1. Fixes: 08a1e650cc ("powerpc: Fixup LPCR:PECE and HEIC setting on POWER9") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Massage change log to avoid referring to LPES0 which is now renamed LPES] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-18powerpc/64: Fix HMI exception on LE with CONFIG_RELOCATABLE=yMichael Ellerman
Prior to commit 2337d207288f ("powerpc/64: CONFIG_RELOCATABLE support for hmi interrupts"), the branch from hmi_exception_early() to hmi_exception_realmode() was just a bl hmi_exception_realmode, which the linker would turn into a bl to the local entry point of hmi_exception_realmode. This was broken when CONFIG_RELOCATABLE=y because hmi_exception_realmode() is not in the low part of the kernel text that is copied down to 0x0. But in fixing that, we added a new bug on little endian kernels. Because the branch is now a bctrl when CONFIG_RELOCATABLE=y, we branch to the global entry point of hmi_exception_realmode(). The global entry point must be called with r12 containing the address of hmi_exception_realmode(), because it uses that value to calculate the TOC value (r2). This may manifest as a checkstop, because we take a junk value from r12 which came from HSRR1, add a small constant to it and then use that as the TOC pointer. The HSRR1 value will have 0x9 as the top nibble, which puts it above RAM and somewhere in MMIO space. Fix it by changing the BRANCH_LINK_TO_FAR() macro to always use r12 to load the label we're branching to. This means r12 will be setup correctly on LE, fixing this bug, and r12 is also volatile across function calls on BE so it's a good choice anyway. Fixes: 2337d207288f ("powerpc/64: CONFIG_RELOCATABLE support for hmi interrupts") Reported-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Acked-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-18powerpc/kprobe: Fix oops when kprobed on 'stdu' instructionRavi Bangoria
If we set a kprobe on a 'stdu' instruction on powerpc64, we see a kernel OOPS: Bad kernel stack pointer cd93c840 at c000000000009868 Oops: Bad kernel stack pointer, sig: 6 [#1] ... GPR00: c000001fcd93cb30 00000000cd93c840 c0000000015c5e00 00000000cd93c840 ... NIP [c000000000009868] resume_kernel+0x2c/0x58 LR [c000000000006208] program_check_common+0x108/0x180 On a 64-bit system when the user probes on a 'stdu' instruction, the kernel does not emulate actual store in emulate_step() because it may corrupt the exception frame. So the kernel does the actual store operation in exception return code i.e. resume_kernel(). resume_kernel() loads the saved stack pointer from memory using lwz, which only loads the low 32-bits of the address, causing the kernel crash. Fix this by loading the 64-bit value instead. Fixes: be96f63375a1 ("powerpc: Split out instruction analysis part of emulate_step()") Cc: stable@vger.kernel.org # v3.18+ Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com> Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Reviewed-by: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> [mpe: Change log massage, add stable tag] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-15powerpc/smp: Replace open coded task affinity logicThomas Gleixner
Init task invokes smp_ops->setup_cpu() from smp_cpus_done(). Init task can run on any online CPU at this point, but the setup_cpu() callback requires to be invoked on the boot CPU. This is achieved by temporarily setting the affinity of the calling user space thread to the requested CPU and reset it to the original affinity afterwards. That's racy vs. CPU hotplug and concurrent affinity settings for that thread resulting in code executing on the wrong CPU and overwriting the new affinity setting. That's actually not a problem in this context as neither CPU hotplug nor affinity settings can happen, but the access to task_struct::cpus_allowed is about to restricted. Replace it with a call to work_on_cpu_safe() which achieves the same result. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Tejun Heo <tj@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: linuxppc-dev@lists.ozlabs.org Cc: "David S. Miller" <davem@davemloft.net> Cc: Len Brown <lenb@kernel.org> Link: http://lkml.kernel.org/r/20170412201042.518053336@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-14powerpc/time: Set ->min_delta_ticks and ->max_delta_ticksNicolai Stange
In preparation for making the clockevents core NTP correction aware, all clockevent device drivers must set ->min_delta_ticks and ->max_delta_ticks rather than ->min_delta_ns and ->max_delta_ns: a clockevent device's rate is going to change dynamically and thus, the ratio of ns to ticks ceases to stay invariant. Make the powerpc arch's clockevent driver initialize these fields properly. This patch alone doesn't introduce any change in functionality as the clockevents core still looks exclusively at the (untouched) ->min_delta_ns and ->max_delta_ns. As soon as this has changed, a followup patch will purge the initialization of ->min_delta_ns and ->max_delta_ns from this driver. Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Oliver O'Halloran <oohall@gmail.com> Cc: linuxppc-dev@lists.ozlabs.org Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2017-04-13powerpc: Introduce msgsnd/doorbell barrier primitivesNicholas Piggin
POWER9 changes requirements and adds new instructions for synchronization. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-13powerpc: Change the doorbell IPI calling conventionNicholas Piggin
Change the doorbell callers to know about their msgsnd addressing, rather than have them set a per-cpu target data tag at boot that gets sent to the cause_ipi functions. The data is only used for doorbell IPI functions, no other IPI types, so it makes sense to keep that detail local to doorbell. Have the platform code understand doorbell IPIs, rather than the interrupt controller code understand them. Platform code can look at capabilities it has available and decide which to use. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-13powerpc/64s: Add SCV FSCR bit for ISA v3.0Nicholas Piggin
Add the bit definition and use it in facility_unavailable_exception() so we can intelligently report the cause if we take a fault for SCV. This doesn't actually enable SCV. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Drop whitespace changes to the existing entries, flush out change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-13powerpc/64s: Add msgp facility unavailable log stringNicholas Piggin
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-12powerpc/tracing: Allow tracing of mmap syscallsBalbir Singh
Currently sys_mmap() and sys_mmap2() (32-bit only), are not visible to the syscall tracing machinery. This means users are not able to see the execution of mmap() syscalls using the syscall tracer. Fix that by using SYSCALL_DEFINE6 for sys_mmap() and sys_mmap2() so that the meta-data associated with these syscalls is visible to the syscall tracer. A side-effect of this change is that the return type has changed from unsigned long to long. However this should have no effect, the only code in the kernel which uses the result of these syscalls is in the syscall return path, which is written in asm and treats the result as unsigned regardless. Example output: cat-3399 [001] .... 196.542410: sys_mmap(addr: 7fff922a0000, len: 20000, prot: 3, flags: 812, fd: 3, offset: 1b0000) cat-3399 [001] .... 196.542443: sys_mmap -> 0x7fff922a0000 cat-3399 [001] .... 196.542668: sys_munmap(addr: 7fff922c0000, len: 6d2c) cat-3399 [001] .... 196.542677: sys_munmap -> 0x0 Signed-off-by: Balbir Singh <bsingharora@gmail.com> [mpe: Massage change log, add detail on return type change] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-12powerpc/mm: Fix swapper_pg_dir size on 64-bit hash w/64K pagesMichael Ellerman
Recently in commit f6eedbba7a26 ("powerpc/mm/hash: Increase VA range to 128TB"), we increased H_PGD_INDEX_SIZE to 15 when we're building with 64K pages. This makes it larger than RADIX_PGD_INDEX_SIZE (13), which means the logic to calculate MAX_PGD_INDEX_SIZE in book3s/64/pgtable.h is wrong. The end result is that the PGD (Page Global Directory, ie top level page table) of the kernel (aka. swapper_pg_dir), is too small. This generally doesn't lead to a crash, as we don't use the full range in normal operation. However if we try to dump the kernel pagetables we can trigger a crash because we walk off the end of the pgd into other memory and eventually try to dereference something bogus: $ cat /sys/kernel/debug/kernel_pagetables Unable to handle kernel paging request for data at address 0xe8fece0000000000 Faulting instruction address: 0xc000000000072314 cpu 0xc: Vector: 380 (Data SLB Access) at [c0000000daa13890] pc: c000000000072314: ptdump_show+0x164/0x430 lr: c000000000072550: ptdump_show+0x3a0/0x430 dar: e802cf0000000000 seq_read+0xf8/0x560 full_proxy_read+0x84/0xc0 __vfs_read+0x6c/0x1d0 vfs_read+0xbc/0x1b0 SyS_read+0x6c/0x110 system_call+0x38/0xfc The root cause is that MAX_PGD_INDEX_SIZE isn't actually computed to be the max of H_PGD_INDEX_SIZE or RADIX_PGD_INDEX_SIZE. To fix that move the calculation into asm-offsets.c where we can do it easily using max(). Fixes: f6eedbba7a26 ("powerpc/mm/hash: Increase VA range to 128TB") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-12Merge branch 'topic/xive' (early part) into nextMichael Ellerman
This merges the arch part of the XIVE support, leaving the final commit with the KVM specific pieces dangling on the branch for Paul to merge via the kvm-ppc tree.
2017-04-11powerpc/powernv: Recover correct PACA on wakeup from a stop on P9 DD1Gautham R. Shenoy
POWER9 DD1.0 hardware has a bug where the SPRs of a thread waking up from stop 0,1,2 with ESL=1 can endup being misplaced in the core. Thus the HSPRG0 of a thread waking up from can contain the paca pointer of its sibling. This patch implements a context recovery framework within threads of a core, by provisioning space in paca_struct for saving every sibling threads's paca pointers. Basically, we should be able to arrive at the right paca pointer from any of the thread's existing paca pointer. At bootup, during powernv idle-init, we save the paca address of every CPU in each one its siblings paca_struct in the slot corresponding to this CPU's index in the core. On wakeup from a stop, the thread will determine its index in the core from the TIR register and recover its PACA pointer by indexing into the correct slot in the provisioned space in the current PACA. Furthermore, ensure that the NVGPRs are restored from the stack on the way out by setting the NAPSTATELOST in paca. [Changelog written with inputs from svaidy@linux.vnet.ibm.com] Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Call it a bug] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-11powerpc: Remove unnecessary includes of asm/debug.hMichael Ellerman
These files don't seem to have any need for asm/debug.h, now that all it includes are the debugger hooks and breakpoint definitions. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-11powerpc: Create asm/debugfs.h and move powerpc_debugfs_root thereMichael Ellerman
powerpc_debugfs_root is the dentry representing the root of the "powerpc" directory tree in debugfs. Currently it sits in asm/debug.h, a long with some other things that have "debug" in the name, but are otherwise unrelated. Pull it out into a separate header, which also includes linux/debugfs.h, and convert all the users to include debugfs.h instead of debug.h. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-10powerpc: Fixup LPCR:PECE and HEIC setting on POWER9Benjamin Herrenschmidt
We need to set LPES in order for normal external interrupts (0x500) to be directed to the guest while running in guest state. We also need HEIC set to prevent them to be sent to the host while in host state. With XIVE the host never gets one of these and wouldn't know how to handle it. All host external interrupts come in via the new hypervisor virtualization interrupts vector. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-07powerpc/smp: Remove migrate_irq() custom implementationBenjamin Herrenschmidt
Some powerpc platforms use this to move IRQs away from a CPU being unplugged. This function has several bugs such as not taking the right locks or failing to NULL check pointers. There's a new generic function doing exactly the same thing without all the bugs, so let's use it instead. mpe: The obvious place for the select of GENERIC_IRQ_MIGRATION is on HOTPLUG_CPU, but that doesn't work. On some configs PM_SLEEP_SMP will select HOTPLUG_CPU even though its dependencies are not met, which means the select of GENERIC_IRQ_MIGRATION doesn't happen. That leads to the build breaking. Fix it by moving the select of GENERIC_IRQ_MIGRATION to SMP. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-06powerpc: Add optional smp_ops->prepare_cpu SMP callbackBenjamin Herrenschmidt
Some platforms (will) need to perform allocations before bringing a new CPU online. Doing it from smp_ops->setup_cpu is the wrong thing to do: - It has no useful failure path (too late) - Calling any allocator will enable interrupts prematurely causing problems with large decrementer among others Instead, add a new callback that is called from __cpu_up (so from the context trying to online the new CPU) at a point where we can safely allocate and handle failures. This will be used by XIVE support. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-05powerpc/64: Fix flush_(d|i)cache_range() called from modulesOliver O'Halloran
When the kernel is compiled to use 64bit ABIv2 the _GLOBAL() macro does not include a global entry point. A function's global entry point is used when the function is called from a different TOC context and in the kernel this typically means a call from a module into the vmlinux (or vice-versa). There are a few exported asm functions declared with _GLOBAL() and calling them from a module will likely crash the kernel since any TOC relative load will yield garbage. flush_icache_range() and flush_dcache_range() are both exported to modules, and use the TOC, so must use _GLOBAL_TOC(). Fixes: 721aeaa9fdf3 ("powerpc: Build little endian ppc64 kernel with ABIv2") Cc: stable@vger.kernel.org # v3.16+ Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-04powerpc: Don't try to fix up misaligned load-with-reservation instructionsPaul Mackerras
In the past, there was only one load-with-reservation instruction, lwarx, and if a program attempted a lwarx on a misaligned address, it would take an alignment interrupt and the kernel handler would emulate it as though it was lwzx, which was not really correct, but benign since it is loading the right amount of data, and the lwarx should be paired with a stwcx. to the same address, which would also cause an alignment interrupt which would result in a SIGBUS being delivered to the process. We now have 5 different sizes of load-with-reservation instruction. Of those, lharx and ldarx cause an immediate SIGBUS by luck since their entries in aligninfo[] overlap instructions which were not fixed up, but lqarx overlaps with lhz and will be emulated as such. lbarx can never generate an alignment interrupt since it only operates on 1 byte. To straighten this out and fix the lqarx case, this adds code to detect the l[hwdq]arx instructions and return without fixing them up, resulting in a SIGBUS being delivered to the process. Cc: stable@vger.kernel.org Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-04powerpc/prom: Increase minimum RMA size to 512MBSukadev Bhattiprolu
When booting very large systems with a large initrd, we run out of space early in boot for either RTAS or the flattened device tree (FDT). Boot fails with messages like: Could not allocate memory for RTAS or No memory for flatten_device_tree (no room) Increasing the minimum RMA size to 512MB fixes the problem. This should not have an impact on smaller LPARs (with 256MB memory), as the firmware will cap the RMA to the memory assigned to the LPAR. Fix is based on input/discussions with Michael Ellerman. Thanks to Praveen K. Pandey for testing on a large system. Reported-by: Praveen K. Pandey <preveen.pandey@in.ibm.com> Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-03debug: Fix __bug_table[] in arch linker scriptsPeter Zijlstra
The kbuild test robot reported this build failure on a number of architectures: > make.cross ARCH=arm > lib/lib.a(bug.o): In function `find_bug': > >> lib/bug.c:135: undefined reference to `__start___bug_table' > >> lib/bug.c:135: undefined reference to `__stop___bug_table' Caused by: 19d436268dde ("debug: Add _ONCE() logic to report_bug()") Which moved the BUG_TABLE from RO_DATA_SECTION() to RW_DATA_SECTION(), but a number of architectures don't use RW_DATA_SECTION(), so they ended up with no __bug_table[] ... Ideally all those would use RW_DATA_SECTION() in their linker scripts, but that's for another day. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kbuild test robot <fengguang.wu@intel.com> Cc: kbuild-all@01.org Cc: tipbuild@zytor.com Link: http://lkml.kernel.org/r/20170330154927.o6qmgfp4bdhrajbm@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-03powerpc/book3s: Print task info if we take a machine check in user modeMichael Ellerman
For an MCE (Machine Check Exception) that hits while in user mode MSR(PR=1), print the task info to the console MCE error log. This may help to identify an application that triggered the MCE. After this patch the MCE console looks like: Severe Machine check interrupt [Recovered] NIP: [0000000010039778] PID: 762 Comm: ebizzy Initiator: CPU Error type: SLB [Multihit] Effective address: 0000000010039778 Severe Machine check interrupt [Not recovered] NIP: [0000000010039778] PID: 763 Comm: ebizzy Initiator: CPU Error type: UE [Page table walk ifetch] Effective address: 0000000010039778 ebizzy[763]: unhandled signal 7 at 0000000010039778 nip 0000000010039778 lr 0000000010001b44 code 30004 Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-03powerpc/book3s: Print the kernel function name in machine checkMahesh Salgaonkar
For D-side errors we print the load/store address that caused the machine check as 'Effective address'. But the instruction that may have caused the machine check can also be helpful, so in addition to printing the NIP, also print the kernel function name as well. After this patch the MCE console log would look like: Severe Machine check interrupt [Recovered] NIP [d00000001bc70194]: init_module+0x194/0x2b0 [bork_kernel] Initiator: CPU Error type: SLB [Parity] Effective address: d000000026de0000 Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-01powerpc/mm: Enable mappings above 128TBAneesh Kumar K.V
Not all user space application is ready to handle wide addresses. It's known that at least some JIT compilers use higher bits in pointers to encode their information. It collides with valid pointers with 512TB addresses and leads to crashes. To mitigate this, we are not going to allocate virtual address space above 128TB by default. But userspace can ask for allocation from full address space by specifying hint address (with or without MAP_FIXED) above 128TB. If hint address set above 128TB, but MAP_FIXED is not specified, we try to look for unmapped area by specified address. If it's already occupied, we look for unmapped area in *full* address space, rather than from 128TB window. This approach helps to easily make application's memory allocator aware about large address space without manually tracking allocated virtual address space. This is going to be a per mmap decision. ie, we can have some mmaps with larger addresses and other that do not. A sample memory layout looks like: 10000000-10010000 r-xp 00000000 fc:00 9057045 /home/max_addr_512TB 10010000-10020000 r--p 00000000 fc:00 9057045 /home/max_addr_512TB 10020000-10030000 rw-p 00010000 fc:00 9057045 /home/max_addr_512TB 10029630000-10029660000 rw-p 00000000 00:00 0 [heap] 7fff834a0000-7fff834b0000 rw-p 00000000 00:00 0 7fff834b0000-7fff83670000 r-xp 00000000 fc:00 9177190 /lib/powerpc64le-linux-gnu/libc-2.23.so 7fff83670000-7fff83680000 r--p 001b0000 fc:00 9177190 /lib/powerpc64le-linux-gnu/libc-2.23.so 7fff83680000-7fff83690000 rw-p 001c0000 fc:00 9177190 /lib/powerpc64le-linux-gnu/libc-2.23.so 7fff83690000-7fff836a0000 rw-p 00000000 00:00 0 7fff836a0000-7fff836c0000 r-xp 00000000 00:00 0 [vdso] 7fff836c0000-7fff83700000 r-xp 00000000 fc:00 9177193 /lib/powerpc64le-linux-gnu/ld-2.23.so 7fff83700000-7fff83710000 r--p 00030000 fc:00 9177193 /lib/powerpc64le-linux-gnu/ld-2.23.so 7fff83710000-7fff83720000 rw-p 00040000 fc:00 9177193 /lib/powerpc64le-linux-gnu/ld-2.23.so 7fffdccf0000-7fffdcd20000 rw-p 00000000 00:00 0 [stack] 1000000000000-1000000010000 rw-p 00000000 00:00 0 1ffff83710000-1ffff83720000 rw-p 00000000 00:00 0 Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-01powerpc/mm/hash: Store addr_limit in PACAAneesh Kumar K.V
We optmize the slice page size array copy to paca by copying only the range based on addr_limit. This will require us to not look at page size array beyond addr_limit in PACA on slb fault. To enable that copy task size to paca which will be used during slb fault. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> [mpe: Rename from task_size to addr_limit, consolidate #ifdefs] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-01powerpc/mm: Add addr_limit to mm_context and use it to derive max slice indexAneesh Kumar K.V
In the followup patch, we will increase the slice array size to handle 512TB range, but will limit the max addr to 128TB. Avoid doing unnecessary computation and avoid doing slice mask related operation above address limit. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-31powerpc/mm: Move copy_mm_to_paca to paca.cAneesh Kumar K.V
We also update the function arg to struct mm_struct. Move this so that function finds the definition of struct mm_struct. No functional change in this patch. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-31powerpc/fadump: Reserve memory at an offset closer to bottom of RAMHari Bathini
Currently, the area to preserve boot memory is reserved at the top of RAM. This leaves fadump vulnerable to memory hot-remove operations. As memory for fadump has to be reserved early in the boot process, fadump can't be registered after a memory hot-remove operation. Though this problem can't be eleminated completely, the impact can be minimized by reserving memory at an offset closer to bottom of the RAM. The offset for fadump memory reservation can be any value greater than fadump boot memory size. Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-30powerpc/vfio_spapr_tce: Add reference counting to iommu_tableAlexey Kardashevskiy
So far iommu_table obejcts were only used in virtual mode and had a single owner. We are going to change this by implementing in-kernel acceleration of DMA mapping requests. The proposed acceleration will handle requests in real mode and KVM will keep references to tables. This adds a kref to iommu_table and defines new helpers to update it. This replaces iommu_free_table() with iommu_tce_table_put() and makes iommu_free_table() static. iommu_tce_table_get() is not used in this patch but it will be in the following patch. Since this touches prototypes, this also removes @node_name parameter as it has never been really useful on powernv and carrying it for the pseries platform code to iommu_free_table() seems to be quite useless as well. This should cause no behavioral change. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Acked-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-30powerpc/iommu/vfio_spapr_tce: Cleanup iommu_table disposalAlexey Kardashevskiy
At the moment iommu_table can be disposed by either calling iommu_table_free() directly or it_ops::free(); the only implementation of free() is in IODA2 - pnv_ioda2_table_free() - and it calls iommu_table_free() anyway. As we are going to have reference counting on tables, we need an unified way of disposing tables. This moves it_ops::free() call into iommu_free_table() and makes use of the latter. The free() callback now handles only platform-specific data. As from now on the iommu_free_table() calls it_ops->free(), we need to have it_ops initialized before calling iommu_free_table() so this moves this initialization in pnv_pci_ioda2_create_table(). This should cause no behavioral change. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Acked-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-30powerpc/powernv/iommu: Add real mode version of iommu_table_ops::exchange()Alexey Kardashevskiy
In real mode, TCE tables are invalidated using special cache-inhibited store instructions which are not available in virtual mode This defines and implements exchange_rm() callback. This does not define set_rm/clear_rm/flush_rm callbacks as there is no user for those - exchange/exchange_rm are only to be used by KVM for VFIO. The exchange_rm callback is defined for IODA1/IODA2 powernv platforms. This replaces list_for_each_entry_rcu with its lockless version as from now on pnv_pci_ioda2_tce_invalidate() can be called in the real mode too. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-28powerpc: Disable HFSCR[TM] if TM is not supportedBenjamin Herrenschmidt
On Power8 & Power9 the early CPU inititialisation in __init_HFSCR() turns on HFSCR[TM] (Hypervisor Facility Status and Control Register [Transactional Memory]), but that doesn't take into account that TM might be disabled by CPU features, or disabled by the kernel being built with CONFIG_PPC_TRANSACTIONAL_MEM=n. So later in boot, when we have setup the CPU features, clear HSCR[TM] if the TM CPU feature has been disabled. We use CPU_FTR_TM_COMP to account for the CONFIG_PPC_TRANSACTIONAL_MEM=n case. Without this a KVM guest might try use TM, even if told not to, and cause an oops in the host kernel. Typically the oops is seen in __kvmppc_vcore_entry() and may or may not be fatal to the host, but is always bad news. In practice all shipping CPU revisions do support TM, and all host kernels we are aware of build with TM support enabled, so no one should actually be able to hit this in the wild. Fixes: 2a3563b023e5 ("powerpc: Setup in HFSCR for POWER8") Cc: stable@vger.kernel.org # v3.10+ Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Tested-by: Sam Bobroff <sam.bobroff@au1.ibm.com> [mpe: Rewrite change log with input from Sam, add Fixes/stable] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-28powerpc: Make /proc/self/stack always print the current stackThadeu Lima de Souza Cascardo
For the current task, the kernel stack would only tell the last time the process was rescheduled, if ever. Use the current stack pointer for the current task. Otherwise, every once in a while, the stacktrace printed when reading /proc/self/stack would look like the process is running in userspace, while it's not, which some may consider as a bug. This is also consistent with some other architectures, like x86 and arm, at least. Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-28powerpc/64: Don't use early_cpu_has_feature() in cpu_ready_for_interrupts()Michael Ellerman
cpu_ready_for_interrupts() is called after feature patching, so there's no need to use early_cpu_has_feature(). Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-21powerpc/64s: POWER8 add missing machine check definitionsNicholas Piggin
POWER8 uses bit 36 in SRR1 like POWER9 for i-side machine checks, and contains several conditions for link timeouts that are not currently handled. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-21powerpc/64s: Data driven machine check handlingNicholas Piggin
Move the handling (corrective action) of machine checks to the table based evaluation. This changes P7 and P8 ERAT flushing from using SLB flush to using ERAT flush. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-21powerpc/64s: Data driven machine check evaluationNicholas Piggin
Have machine types define i-side and d-side tables to describe their machine check encodings, and match entries to evaluate (for reporting) machine checks. Functionality is mostly unchanged (tested with a userspace harness), but it does make a change in that it no longer records DAR as the effective address for those errors where it is specified to be invalid (which is a reporting change only). Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-21powerpc/64s: Move POWER machine check defines into mce_power.cNicholas Piggin
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-21powerpc/64s: Clean up machine check recovery flushingNicholas Piggin
Use the flush function introduced with the POWER9 machine check handler for POWER7 and 8, rather than open coding it multiple times in callers. There is a specific ERAT flush type introduced for POWER9, but the POWER7-8 ERAT errors continue to do SLB flushing (which also flushes ERAT), so as not to introduce functional changes with this cleanup patch. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-21powerpc/64s: Machine check print NIPNicholas Piggin
Print the faulting address of the machine check that may help with debugging. The effective address reported can be a target memory address rather than the faulting instruction address. Fix up a dangling bracket while here. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-21powerpc/32: Remove Mac-on-Linux/rtlinux hooksBen Hutchings
The symbols exported for use by MOL/rtlinux aren't getting CRCs and I was about to fix that. But MOL is dead upstream, and the latest work on it was to make it use KVM instead of its own kernel module. So remove them instead. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-20powerpc/64s: Fix idle wakeup potential to clobber registersNicholas Piggin
We concluded there may be a window where the idle wakeup code could get to pnv_wakeup_tb_loss() (which clobbers non-volatile GPRs), but the hardware may set SRR1[46:47] to 01b (no state loss) which would result in the wakeup code failing to restore non-volatile GPRs. I was not able to trigger this condition with trivial tests on real hardware or simulator, but the ISA (at least 2.07) seems to allow for it, and Gautham says that it can happen if there is an exception pending when the sleep/winkle instruction is executed. Fixes: 1706567117ba ("powerpc/kvm: make hypervisor state restore a function") Cc: stable@vger.kernel.org # v4.8+ Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Acked-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-20powerpc/ftrace: Add prototype for prepare_ftrace_return()Tobin C. Harding
Sparse emits a warning: symbol 'prepare_ftrace_return' was not declared. Should it be static? prepare_ftrace_return() is called from assembler and should not be static. Add a prototype for it to asm-prototypes.h and include that in ftrace.c. Signed-off-by: Tobin C. Harding <me@tobin.cc> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-20powerpc/swsusp: Include suspend.h to silence sparse warningsTobin C. Harding
Sparse emits two symbol not declared warnings for swsusp.c. The two functions, save_processor_state() and restore_processor_state() are declared already in suspend.h, so include it. Signed-off-by: Tobin C. Harding <me@tobin.cc> Reviewed-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>