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| * | | powerpc/64s: Avoid cpabort in context switch when possibleNicholas Piggin2017-06-152-10/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The ISA v3.0B copy-paste facility only requires cpabort when switching to a process that has foreign real addresses mapped (direct access to accelerators), to clear a potential copy buffer filled by a previous thread. There is no accelerator driver implemented yet, so cpabort can be removed. It can be be re-added when a driver is implemented. POWER9 DD1 requires the copy buffer to always be cleared on context switch, but if accelerators are not in use, then an unpaired copy from a dummy region is sufficient to clear data out of the copy buffer. This increases context switch performance by about 5% on POWER9. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/64: Drop explicit hwsync in context switchNicholas Piggin2017-06-151-6/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The sync (aka. hwsync, aka. heavyweight sync) in the context switch code to prevent MMIO access being reordered from the point of view of a single process if it gets migrated to a different CPU is not required because there is an hwsync performed earlier in the context switch path. Comment this so it's clear enough if anything changes on the scheduler or the powerpc sides. Remove the hwsync from _switch. This improves context switch performance by 2-3% on POWER8. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/64: Drop reservation-clearing ldarx in context switchNicholas Piggin2017-06-151-8/+3Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is no need to explicitly break the reservation in _switch, because we are guaranteed that the context switch path will include a larx/stcx. Comment the guarantee and remove the reservation clear from _switch. This is worth 1-2% in context switch performance. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/64s: Leave interrupts hard enabled in context switch for radixNicholas Piggin2017-06-152-6/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 4387e9ff25 ("[POWERPC] Fix PMU + soft interrupt disable bug") hard disabled interrupts over the low level context switch, because the SLB management can't cope with a PMU interrupt accesing the stack in that window. Radix based kernel mapping does not use the SLB so it does not require interrupts hard disabled here. This is worth 1-2% in context switch performance on POWER9. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/64: Avoid restore_math call if possible in syscall exitNicholas Piggin2017-06-152-19/+47
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The syscall exit code that branches to restore_math is quite heavy on Book3S, consisting of 2 mtmsr instructions. Threads that don't use both FP and vector can get caught here if the kernel ever uses FP or vector. Lazy-FP/vec context switching also trips this case. So check for lazy FP and vector before switching RI for restore_math. Move most of this case out of line. For threads that do want to restore math registers, the MSR switches are still suboptimal. Future direction may be to use a soft-RI bit to avoid MSR switches in kernel (similar to soft-EE), but for now at least the no-restore POWER9 context switch rate increases by about 5% due to sched_yield(2) return performance. I haven't constructed a test to measure the syscall cost. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/64s: Optimize hypercall/syscall entryNicholas Piggin2017-06-151-37/+97
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After bc3551257a ("powerpc/64: Allow for relocation-on interrupts from guest to host"), a getppid() system call goes from 307 cycles to 358 cycles (+17%) on POWER8. This is due significantly to the scratch SPR used by the hypercall check. It turns out there are a some volatile registers common to both system call and hypercall (in particular, r12, cr0, ctr), which can be used to avoid the SPR and some other overheads. This brings getppid to 320 cycles (+4%). Testing hcall entry performance by running "sc 1" in guest userspace before this patch is 854 cycles, afterwards is 826. Also a small win there. POWER9 syscall is improved by about the same amount, hcall not tested. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | Revert "powerpc: Handle simultaneous interrupts at once"Michael Ellerman2017-06-151-5/+1Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit 45cb08f4791ce6a15c54598b4cb73db4b4b8294f. For some reason this is causing IRQ problems on Freescale Book3E machines, eg on my p5020ds: irq 25: nobody cared (try booting with the "irqpoll" option) CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.12.0-rc3-gcc-6.3.1-00037-g45cb08f4791c #624 Call Trace: [c0000000fffdbb10] [c00000000049962c] .dump_stack+0xa8/0xe8 (unreliable) [c0000000fffdbba0] [c0000000000babf4] .__report_bad_irq+0x54/0x140 [c0000000fffdbc40] [c0000000000bb11c] .note_interrupt+0x324/0x380 [c0000000fffdbd00] [c0000000000b7110] .handle_irq_event_percpu+0x68/0x88 [c0000000fffdbd90] [c0000000000b718c] .handle_irq_event+0x5c/0xa8 [c0000000fffdbe10] [c0000000000bc01c] .handle_fasteoi_irq+0xe4/0x298 [c0000000fffdbe90] [c0000000000b59c4] .generic_handle_irq+0x50/0x74 [c0000000fffdbf10] [c0000000000075d8] .__do_irq+0x74/0x1f0 [c0000000fffdbf90] [c0000000000189f8] .call_do_irq+0x14/0x24 [c0000000f7173060] [c0000000000077e4] .do_IRQ+0x90/0x120 [c0000000f7173100] [c00000000001d93c] exc_0x500_common+0xfc/0x100 --- interrupt: 501 at .prepare_to_wait_event+0xc/0x14c LR = .fsl_elbc_run_command+0xc8/0x23c [c0000000f71734d0] [c00000000065f418] .nand_reset+0xb8/0x168 [c0000000f7173560] [c00000000065fec4] .nand_scan_ident+0x2b0/0x1638 [c0000000f7173650] [c000000000666cd8] .fsl_elbc_nand_probe+0x34c/0x5f0 ata2: SATA link up 1.5 Gbps (SStatus 113 SControl 300) [c0000000f7173750] [c0000000005a3c60] .platform_drv_probe+0x64/0xb0 [c0000000f71737d0] [c0000000005a12e0] .really_probe+0x290/0x334 [c0000000f7173870] [c0000000005a14a0] .__driver_attach+0x11c/0x120 [c0000000f7173900] [c00000000059e6a0] .bus_for_each_dev+0x98/0xfc [c0000000f71739a0] [c0000000005a0b3c] .driver_attach+0x34/0x4c [c0000000f7173a20] [c0000000005a04b0] .bus_add_driver+0x1ac/0x2e0 [c0000000f7173ac0] [c0000000005a2170] .driver_register+0x94/0x160 [c0000000f7173b40] [c0000000005a3be0] .__platform_driver_register+0x60/0x7c [c0000000f7173bc0] [c000000000d6aab4] .fsl_elbc_nand_driver_init+0x24/0x38 [c0000000f7173c30] [c000000000001934] .do_one_initcall+0x68/0x1b8 [c0000000f7173d00] [c000000000d210f8] .kernel_init_freeable+0x260/0x338 [c0000000f7173db0] [c0000000000021b0] .kernel_init+0x20/0xe70 [c0000000f7173e30] [c0000000000009bc] .ret_from_kernel_thread+0x58/0x9c handlers: [<c000000000ed85c8>] .fsl_lbc_ctrl_irq Disabling IRQ #25 Ben also had concerns with the implementation being potentially slow on some PICs, so revert it for now. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/64s: Machine check handle ifetch from foreign real address for POWER9Nicholas Piggin2017-06-062-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The i-side 0111b machine check, which is "Instruction Fetch to foreign address space", was missed by 7b9f71f974 ("powerpc/64s: POWER9 machine check handler"). The POWER9 processor core considers host real addresses with a nonzero value in RA(8:12) as foreign address space, accessible only by the copy and paste instructions. The copy and paste instruction pair can be used to invoke the Nest accelerators via the Virtual Accelerator Switchboard (VAS). It is an error for any regular load/store or ifetch to go to a foreign addresses. When relocation is on, this causes an MMU exception. When relocation is off, a machine check exception. It is possible to trigger this machine check by branching to a foreign address with MSR[IR]=0. Fixes: 7b9f71f974a1 ("powerpc/64s: POWER9 machine check handler") Reported-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/fadump: Set an upper limit for boot memory sizeHari Bathini2017-06-021-1/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | By default, 5% of system RAM is reserved for preserving boot memory. Alternatively, a user can specify the amount of memory to reserve. See Documentation/powerpc/firmware-assisted-dump.txt for details. In addition to the memory reserved for preserving boot memory, some more memory is reserved, to save HPTE region, CPU state data and ELF core headers. Memory Reservation during first kernel looks like below: Low memory Top of memory 0 boot memory size | | | |<--Reserved dump area -->| V V | Permanent Reservation V +-----------+----------/ /----------+---+----+-----------+----+ | | |CPU|HPTE| DUMP |ELF | +-----------+----------/ /----------+---+----+-----------+----+ | ^ | | \ / ------------------------------------------- Boot memory content gets transferred to reserved area by firmware at the time of crash This implicitly means that the sum of the sizes of boot memory, CPU state data, HPTE region, DUMP preserving area and ELF core headers can't be greater than the total memory size. But currently, a user is allowed to specify any value as boot memory size. So, the above rule is violated when a boot memory size around 50% of the total available memory is specified. As the kernel is not handling this currently, it may lead to undefined behavior. Fix it by setting an upper limit for boot memory size to 25% of the total available memory. Also, instead of using memblock_end_of_DRAM(), which doesn't take the holes, if any, in the memory layout into account, use memblock_phys_mem_size() to calculate the percentage of total available memory. Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/fadump: Update comment about offset where fadump is reservedHari Bathini2017-06-021-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With commit f6e6bedb7731 ("powerpc/fadump: Reserve memory at an offset closer to bottom of RAM"), memory for fadump is no longer reserved at the top of RAM. But there are still a few places which say so. Change them appropriately. Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/fadump: Add a warning when 'fadump_reserve_mem=' is usedHari Bathini2017-06-021-0/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With commit 11550dc0a00b ("powerpc/fadump: reuse crashkernel parameter for fadump memory reservation"), 'fadump_reserve_mem=' parameter is deprecated in favor of 'crashkernel=' parameter. Add a warning if 'fadump_reserve_mem=' is still used. Fixes: 11550dc0a00b ("powerpc/fadump: reuse crashkernel parameter for fadump memory reservation") Suggested-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com> [mpe: Unsplit long printk strings] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/fadump: Return error when fadump registration failsMichal Suchanek2017-06-021-8/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - log an error message when registration fails and no error code listed in the switch is returned - translate the hv error code to posix error code and return it from fw_register - return the posix error code from fw_register to the process writing to sysfs - return EEXIST on re-registration - return success on deregistration when fadump is not registered - return ENODEV when no memory is reserved for fadump Signed-off-by: Michal Suchanek <msuchanek@suse.de> Tested-by: Hari Bathini <hbathini@linux.vnet.ibm.com> [mpe: Use pr_err() to shrink the error print] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc: Handle simultaneous interrupts at onceChristophe Leroy2017-06-021-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It often happens to have simultaneous interrupts, for instance when having double Ethernet attachment. With the current implementation, we suffer the cost of kernel entry/exit for each interrupt. This patch introduces a loop in __do_irq() to handle all interrupts at once before returning. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/40x: Clear MSR_DR in one insn instead of twoChristophe Leroy2017-06-021-4/+2Star
| | | | | | | | | | | | | | | | | | | | Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc: Link warning for orphan sectionsNicholas Piggin2017-05-301-2/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add --orphan-handling=warn to final link flags. This ensures we can handle all sections explicitly. This would have caught subtle breakage such as 7de3b27bac47da9de08409df1d69664acbb72197 at build-time. Also bring existing orphan sections into the fold: - .text.hot and .text.unlikely are compiler generated sections. - .sdata2, .dynsbss, .plt are used by PPC32 - We previously did not specify DWARF_DEBUG or STABS_DEBUG - DWARF_DEBUG did not include all DWARF sections that can be emitted - A number of sections are unused and can be discarded. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/64: Tool to check head sections location sanityNicholas Piggin2017-05-301-22/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use a tool to check that the location of "fixed sections" are where we expected them to be, which catches cases the linker script can't (stubs being added to start of .text section), and which ends up being neater. Sample output: ERROR: start_text address is c000000000008100, should be c000000000008000 ERROR: see comments in arch/powerpc/tools/head_check.sh Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Fold in fix from Nick for 4.6 era toolchains] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/64: Handle linker stubs in low .text codeNicholas Piggin2017-05-301-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Very large kernels may require linker stubs for branches from HEAD text code. The linker may place these stubs before the HEAD text sections, which breaks the assumption that HEAD text is located at 0 (or the .text section being located at 0x7000/0x8000 on Book3S kernels). Provide an option to create a small section just before the .text section with an empty 256 - 4 bytes, and adjust the start of the .text section to match. The linker will tend to put stubs in that section and not break our relative-to-absolute offset assumptions. This causes a small waste of space on common kernels, but allows large kernels to build and boot. For now, it is an EXPERT config option, defaulting to =n, but a reference is provided for it in the build-time check for such breakage. This is good enough for allyesconfig and custom users / hackers. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/64: Place sfpr section explicitly with the linker scriptNicholas Piggin2017-05-301-0/+8
| | | | | | | | | | | | | | | | | | | | Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/[booke|4xx]: Don't clobber TCR[WP] when setting TCR[DIE]Ivan Mikhaylov2017-05-301-3/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Prevent a kernel panic caused by unintentionally clearing TCR watchdog bits. At this point in the kernel boot, the watchdog may have already been enabled by u-boot. The original code's attempt to write to the TCR register results in an inadvertent clearing of the watchdog configuration bits, causing the 476 to reset. Signed-off-by: Ivan Mikhaylov <ivan@de.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/powernv/idle: Use Requested Level for restoring state on P9 DD1Gautham R. Shenoy2017-05-302-1/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On Power9 DD1 due to a hardware bug the Power-Saving Level Status field (PLS) of the PSSCR for a thread waking up from a deep state can under-report if some other thread in the core is in a shallow stop state. The scenario in which this can manifest is as follows: 1) All the threads of the core are in deep stop. 2) One of the threads is woken up. The PLS for this thread will correctly reflect that it is waking up from deep stop. 3) The thread that has woken up now executes a shallow stop. 4) When some other thread in the core is woken, its PLS will reflect the shallow stop state. Thus, the subsequent thread for which the PLS is under-reporting the wakeup state will not restore the hypervisor resources. Hence, on DD1 systems, use the Requested Level (RL) field as a workaround to restore the contents of the hypervisor resources on the wakeup from the stop state. Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/powernv/idle: Restore LPCR on wakeup from deep-stopGautham R. Shenoy2017-05-301-3/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On wakeup from a deep stop state which is supposed to lose the hypervisor state, we don't restore the LPCR to the old value but set it to a "sane" value via cur_cpu_spec->cpu_restore(). The problem is that the "sane" value doesn't include UPRT and the HR bits which are required to run correctly in Radix mode. Fix this on POWER9 onwards by restoring the LPCR value whatever it was before executing the stop instruction. Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/powernv/idle: Decouple Timebase restore & Per-core SPRs restoreGautham R. Shenoy2017-05-301-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On POWER8, in case of - nap: both timebase and hypervisor state is retained. - fast-sleep: timebase is lost. But the hypervisor state is retained. - winkle: timebase and hypervisor state is lost. Hence, the current code for handling exit from a idle state assumes that if the timebase value is retained, then so is the hypervisor state. Thus, the current code doesn't restore per-core hypervisor state in such cases. But that is no longer the case on POWER9 where we do have stop states in which timebase value is retained, but the hypervisor state is lost. So we have to ensure that the per-core hypervisor state gets restored in such cases. Fix this by ensuring that even in the case when timebase is retained, we explicitly check if we are waking up from a deep stop that loses per-core hypervisor state (indicated by cr4 being eq or gt), and if this is the case, we restore the per-core hypervisor state. Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | | | Merge tag 'dma-mapping-4.13' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds2017-07-073-27/+24Star
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull dma-mapping infrastructure from Christoph Hellwig: "This is the first pull request for the new dma-mapping subsystem In this new subsystem we'll try to properly maintain all the generic code related to dma-mapping, and will further consolidate arch code into common helpers. This pull request contains: - removal of the DMA_ERROR_CODE macro, replacing it with calls to ->mapping_error so that the dma_map_ops instances are more self contained and can be shared across architectures (me) - removal of the ->set_dma_mask method, which duplicates the ->dma_capable one in terms of functionality, but requires more duplicate code. - various updates for the coherent dma pool and related arm code (Vladimir) - various smaller cleanups (me)" * tag 'dma-mapping-4.13' of git://git.infradead.org/users/hch/dma-mapping: (56 commits) ARM: dma-mapping: Remove traces of NOMMU code ARM: NOMMU: Set ARM_DMA_MEM_BUFFERABLE for M-class cpus ARM: NOMMU: Introduce dma operations for noMMU drivers: dma-mapping: allow dma_common_mmap() for NOMMU drivers: dma-coherent: Introduce default DMA pool drivers: dma-coherent: Account dma_pfn_offset when used with device tree dma: Take into account dma_pfn_offset dma-mapping: replace dmam_alloc_noncoherent with dmam_alloc_attrs dma-mapping: remove dmam_free_noncoherent crypto: qat - avoid an uninitialized variable warning au1100fb: remove a bogus dma_free_nonconsistent call MAINTAINERS: add entry for dma mapping helpers powerpc: merge __dma_set_mask into dma_set_mask dma-mapping: remove the set_dma_mask method powerpc/cell: use the dma_supported method for ops switching powerpc/cell: clean up fixed mapping dma_ops initialization tile: remove dma_supported and mapping_error methods xen-swiotlb: remove xen_swiotlb_set_dma_mask arm: implement ->dma_supported instead of ->set_dma_mask mips/loongson64: implement ->dma_supported instead of ->set_dma_mask ...
| * | | | powerpc: merge __dma_set_mask into dma_set_maskChristoph Hellwig2017-06-281-9/+4Star
| | | | | | | | | | | | | | | | | | | | Signed-off-by: Christoph Hellwig <hch@lst.de>
| * | | | dma-mapping: remove the set_dma_mask methodChristoph Hellwig2017-06-281-4/+0Star
| | | | | | | | | | | | | | | | | | | | Signed-off-by: Christoph Hellwig <hch@lst.de>
| * | | | powerpc: implement ->mapping_errorChristoph Hellwig2017-06-282-14/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | DMA_ERROR_CODE is going to go away, so don't rely on it. Instead define a ->mapping_error method for all IOMMU based dma operation instances. The direct ops don't ever return an error and don't need a ->mapping_error method. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Michael Ellerman <mpe@ellerman.id.au>
* | | | | Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2017-07-072-0/+4
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull KVM updates from Paolo Bonzini: "PPC: - Better machine check handling for HV KVM - Ability to support guests with threads=2, 4 or 8 on POWER9 - Fix for a race that could cause delayed recognition of signals - Fix for a bug where POWER9 guests could sleep with interrupts pending. ARM: - VCPU request overhaul - allow timer and PMU to have their interrupt number selected from userspace - workaround for Cavium erratum 30115 - handling of memory poisonning - the usual crop of fixes and cleanups s390: - initial machine check forwarding - migration support for the CMMA page hinting information - cleanups and fixes x86: - nested VMX bugfixes and improvements - more reliable NMI window detection on AMD - APIC timer optimizations Generic: - VCPU request overhaul + documentation of common code patterns - kvm_stat improvements" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (124 commits) Update my email address kvm: vmx: allow host to access guest MSR_IA32_BNDCFGS x86: kvm: mmu: use ept a/d in vmcs02 iff used in vmcs12 kvm: x86: mmu: allow A/D bits to be disabled in an mmu x86: kvm: mmu: make spte mmio mask more explicit x86: kvm: mmu: dead code thanks to access tracking KVM: PPC: Book3S: Fix typo in XICS-on-XIVE state saving code KVM: PPC: Book3S HV: Close race with testing for signals on guest entry KVM: PPC: Book3S HV: Simplify dynamic micro-threading code KVM: x86: remove ignored type attribute KVM: LAPIC: Fix lapic timer injection delay KVM: lapic: reorganize restart_apic_timer KVM: lapic: reorganize start_hv_timer kvm: nVMX: Check memory operand to INVVPID KVM: s390: Inject machine check into the nested guest KVM: s390: Inject machine check into the guest tools/kvm_stat: add new interactive command 'b' tools/kvm_stat: add new command line switch '-i' tools/kvm_stat: fix error on interactive command 'g' KVM: SVM: suppress unnecessary NMI singlestep on GIF=0 and nested exit ...
| * | | | | powerpc/book3s: EXPORT_SYMBOL_GPL machine_check_print_event_infoMahesh Salgaonkar2017-06-211-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It will be used in arch/powerpc/kvm/book3s_hv.c KVM module. Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
| * | | | | KVM: PPC: Book3S HV: Add new capability to control MCE behaviourAravinda Prasad2017-06-211-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This introduces a new KVM capability to control how KVM behaves on machine check exception (MCE) in HV KVM guests. If this capability has not been enabled, KVM redirects machine check exceptions to guest's 0x200 vector, if the address in error belongs to the guest. With this capability enabled, KVM will cause a guest exit with the exit reason indicating an NMI. The new capability is required to avoid problems if a new kernel/KVM is used with an old QEMU, running a guest that doesn't issue "ibm,nmi-register". As old QEMU does not understand the NMI exit type, it treats it as a fatal error. However, the guest could have handled the machine check error if the exception was delivered to guest's 0x200 interrupt vector instead of NMI exit in case of old QEMU. [paulus@ozlabs.org - Reworded the commit message to be clearer, enable only on HV KVM.] Signed-off-by: Aravinda Prasad <aravinda@linux.vnet.ibm.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
| * | | | | KVM: PPC: Book3S HV: Virtualize doorbell facility on POWER9Paul Mackerras2017-06-191-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On POWER9, we no longer have the restriction that we had on POWER8 where all threads in a core have to be in the same partition, so the CPU threads are now independent. However, we still want to be able to run guests with a virtual SMT topology, if only to allow migration of guests from POWER8 systems to POWER9. A guest that has a virtual SMT mode greater than 1 will expect to be able to use the doorbell facility; it will expect the msgsndp and msgclrp instructions to work appropriately and to be able to read sensible values from the TIR (thread identification register) and DPDES (directed privileged doorbell exception status) special-purpose registers. However, since each CPU thread is a separate sub-processor in POWER9, these instructions and registers can only be used within a single CPU thread. In order for these instructions to appear to act correctly according to the guest's virtual SMT mode, we have to trap and emulate them. We cause them to trap by clearing the HFSCR_MSGP bit in the HFSCR register. The emulation is triggered by the hypervisor facility unavailable interrupt that occurs when the guest uses them. To cause a doorbell interrupt to occur within the guest, we set the DPDES register to 1. If the guest has interrupts enabled, the CPU will generate a doorbell interrupt and clear the DPDES register in hardware. The DPDES hardware register for the guest is saved in the vcpu->arch.vcore->dpdes field. Since this gets written by the guest exit code, other VCPUs wishing to cause a doorbell interrupt don't write that field directly, but instead set a vcpu->arch.doorbell_request flag. This is consumed and set to 0 by the guest entry code, which then sets DPDES to 1. Emulating reads of the DPDES register is somewhat involved, because it requires reading the doorbell pending interrupt status of all of the VCPU threads in the virtual core, and if any of those VCPUs are running, their doorbell status is only up-to-date in the hardware DPDES registers of the CPUs where they are running. In order to get a reasonable approximation of the current doorbell status, we send those CPUs an IPI, causing an exit from the guest which will update the vcpu->arch.vcore->dpdes field. We then use that value in constructing the emulated DPDES register value. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
| * | | | | KVM: PPC: Book3S HV: Context-switch HFSCR between host and guest on POWER9Paul Mackerras2017-06-191-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds code to allow us to use a different value for the HFSCR (Hypervisor Facilities Status and Control Register) when running the guest from that which applies in the host. The reason for doing this is to allow us to trap the msgsndp instruction and related operations in future so that they can be virtualized. We also save the value of HFSCR when a hypervisor facility unavailable interrupt occurs, because the high byte of HFSCR indicates which facility the guest attempted to access. We save and restore the host value on guest entry/exit because some bits of it affect host userspace execution. We only do all this on POWER9, not on POWER8, because we are not intending to virtualize any of the facilities controlled by HFSCR on POWER8. In particular, the HFSCR bit that controls execution of msgsndp and related operations does not exist on POWER8. The HFSCR doesn't exist at all on POWER7. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
* | | | | | Merge tag 'pstore-v4.13-rc1' of ↵Linus Torvalds2017-07-051-9/+5Star
|\ \ \ \ \ \ | |_|_|_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull pstore updates from Kees Cook: "Various fixes and tweaks for the pstore subsystem. Highlights: - use memdup_user() instead of open-coded copies (Geliang Tang) - fix record memory leak during initialization (Douglas Anderson) - avoid confused compressed record warning (Ankit Kumar) - prepopulate record timestamp and remove redundant logic from backends" * tag 'pstore-v4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: powerpc/nvram: use memdup_user pstore: use memdup_user pstore: Fix format string to use %u for record id pstore: Populate pstore record->time field pstore: Create common record initializer efi-pstore: Refactor erase routine pstore: Avoid potential infinite loop pstore: Fix leaked pstore_record in pstore_get_backend_records() pstore: Don't warn if data is uncompressed and type is not PSTORE_TYPE_DMESG
| * | | | | powerpc/nvram: use memdup_userGeliang Tang2017-06-281-9/+5Star
| | |_|/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | Use memdup_user() helper instead of open-coding to simplify the code. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org>
* | | | | Merge branch 'smp-hotplug-for-linus' of ↵Linus Torvalds2017-07-041-1/+1
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull SMP hotplug updates from Thomas Gleixner: "This update is primarily a cleanup of the CPU hotplug locking code. The hotplug locking mechanism is an open coded RWSEM, which allows recursive locking. The main problem with that is the recursive nature as it evades the full lockdep coverage and hides potential deadlocks. The rework replaces the open coded RWSEM with a percpu RWSEM and establishes full lockdep coverage that way. The bulk of the changes fix up recursive locking issues and address the now fully reported potential deadlocks all over the place. Some of these deadlocks have been observed in the RT tree, but on mainline the probability was low enough to hide them away." * 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits) cpu/hotplug: Constify attribute_group structures powerpc: Only obtain cpu_hotplug_lock if called by rtasd ARM/hw_breakpoint: Fix possible recursive locking for arch_hw_breakpoint_init cpu/hotplug: Remove unused check_for_tasks() function perf/core: Don't release cred_guard_mutex if not taken cpuhotplug: Link lock stacks for hotplug callbacks acpi/processor: Prevent cpu hotplug deadlock sched: Provide is_percpu_thread() helper cpu/hotplug: Convert hotplug locking to percpu rwsem s390: Prevent hotplug rwsem recursion arm: Prevent hotplug rwsem recursion arm64: Prevent cpu hotplug rwsem recursion kprobes: Cure hotplug lock ordering issues jump_label: Reorder hotplug lock and jump_label_lock perf/tracing/cpuhotplug: Fix locking order ACPI/processor: Use cpu_hotplug_disable() instead of get_online_cpus() PCI: Replace the racy recursion prevention PCI: Use cpu_hotplug_disable() instead of get_online_cpus() perf/x86/intel: Drop get_online_cpus() in intel_snb_check_microcode() x86/perf: Drop EXPORT of perf_check_microcode ...
| * | | | | powerpc: Only obtain cpu_hotplug_lock if called by rtasdThiago Jung Bauermann2017-06-231-1/+1
| | |/ / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Calling arch_update_cpu_topology from a CPU hotplug state machine callback hits a deadlock because the function tries to get a read lock on cpu_hotplug_lock while the state machine still holds a write lock on it. Since all callers of arch_update_cpu_topology except rtasd already hold cpu_hotplug_lock, this patch changes the function to use stop_machine_cpuslocked and creates a separate function for rtasd which still tries to obtain the lock. Michael Bringmann investigated the bug and provided a detailed analysis of the deadlock on this previous RFC for an alternate solution: Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Cc: John Allen <jallen@linux.vnet.ibm.com> Cc: Michael Bringmann <mwb@linux.vnet.ibm.com> Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com> Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/r/1497996510-4032-1-git-send-email-bauerman@linux.vnet.ibm.com Link: https://patchwork.ozlabs.org/patch/771293/
* | | | | Merge branch 'linus' into sched/core, to pick up fixesIngo Molnar2017-06-244-20/+98
|\ \ \ \ \ | | |_|_|/ | |/| | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | powerpc/64: Initialise thread_info for emergency stacksNicholas Piggin2017-06-231-3/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Emergency stacks have their thread_info mostly uninitialised, which in particular means garbage preempt_count values. Emergency stack code runs with interrupts disabled entirely, and is used very rarely, so this has been unnoticed so far. It was found by a proposed new powerpc watchdog that takes a soft-NMI directly from the masked_interrupt handler and using the emergency stack. That crashed at BUG_ON(in_nmi()) in nmi_enter(). preempt_count()s were found to be garbage. To fix this, zero the entire THREAD_SIZE allocation, and initialize the thread_info. Cc: stable@vger.kernel.org Reported-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Move it all into setup_64.c, use a function not a macro. Fix crashes on Cell by setting preempt_count to 0 not HARDIRQ_OFFSET] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | powerpc/64s: Handle data breakpoints in Radix modeNaveen N. Rao2017-06-161-4/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On Power9, trying to use data breakpoints throws the splat shown below. This is because the check for a data breakpoint in DSISR is in do_hash_page(), which is not called when in Radix mode. Unable to handle kernel paging request for data at address 0xc000000000e19218 Faulting instruction address: 0xc0000000001155e8 cpu 0x0: Vector: 300 (Data Access) at [c0000000ef1e7b20] pc: c0000000001155e8: find_pid_ns+0x48/0xe0 lr: c000000000116ac4: find_task_by_vpid+0x44/0x90 sp: c0000000ef1e7da0 msr: 9000000000009033 dar: c000000000e19218 dsisr: 400000 Move the check to handle_page_fault() so as to catch data breakpoints in both Hash and Radix MMU modes. We have to change the check in do_hash_page() against 0xa410 to use 0xa450, so as to include the value of (DSISR_DABRMATCH << 16). There are two sites that call handle_page_fault() when in Radix, both already pass DSISR in r4. Fixes: caca285e5ab4 ("powerpc/mm/radix: Use STD_MMU_64 to properly isolate hash related code") Cc: stable@vger.kernel.org # v4.7+ Reported-by: Shriya R. Kulkarni <shriykul@in.ibm.com> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> [mpe: Fix the fall-through case on hash, we need to reload DSISR] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | powerpc/kprobes: Skip livepatch_handler() for jprobesNaveen N. Rao2017-06-162-5/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ftrace_caller() depends on a modified regs->nip to detect if a certain function has been livepatched. However, with KPROBES_ON_FTRACE, it is possible for regs->nip to have been modified by the kprobes pre_handler (jprobes, for instance). In this case, we do not want to invoke the livepatch_handler so as not to consume the livepatch stack. To distinguish between the two (kprobes and livepatch), we check if there is an active kprobe on the current function. If there is, then we know for sure that it must have modified the NIP as we don't support livepatching a kprobe'd function. In this case, we simply skip the livepatch_handler and branch to the new NIP. Otherwise, the livepatch_handler is invoked. Fixes: ead514d5fb30 ("powerpc/kprobes: Add support for KPROBES_ON_FTRACE") Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | powerpc/ftrace: Pass the correct stack pointer for DYNAMIC_FTRACE_WITH_REGSNaveen N. Rao2017-06-161-8/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For DYNAMIC_FTRACE_WITH_REGS, we should be passing-in the original set of registers in pt_regs, to capture the state _before_ ftrace_caller. However, we are instead passing the stack pointer *after* allocating a stack frame in ftrace_caller. Fix this by saving the proper value of r1 in pt_regs. Also, use SAVE_10GPRS() to simplify the code. Fixes: 153086644fd1 ("powerpc/ftrace: Add support for -mprofile-kernel ftrace ABI") Cc: stable@vger.kernel.org # v4.6+ Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | powerpc/kprobes: Pause function_graph tracing during jprobes handlingNaveen N. Rao2017-06-161-0/+11
| | |_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fixes a crash when function_graph and jprobes are used together. This is essentially commit 237d28db036e ("ftrace/jprobes/x86: Fix conflict between jprobes and function graph tracing"), but for powerpc. Jprobes breaks function_graph tracing since the jprobe hook needs to use jprobe_return(), which never returns back to the hook, but instead to the original jprobe'd function. The solution is to momentarily pause function_graph tracing before invoking the jprobe hook and re-enable it when returning back to the original jprobe'd function. Fixes: 6794c78243bf ("powerpc64: port of the function graph tracer") Cc: stable@vger.kernel.org # v2.6.30+ Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | | | Merge branch 'WIP.sched/core' into sched/coreIngo Molnar2017-06-206-14/+58
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: kernel/sched/Makefile Pick up the waitqueue related renames - it didn't get much feedback, so it appears to be uncontroversial. Famous last words? ;-) Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | powerpc/mm/4k: Limit 4k page size config to 64TB virtual address spaceAneesh Kumar K.V2017-06-081-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Supporting 512TB requires us to do a order 3 allocation for level 1 page table (pgd). This results in page allocation failures with certain workloads. For now limit 4k linux page size config to 64TB. Fixes: f6eedbba7a26 ("powerpc/mm/hash: Increase VA range to 128TB") Reported-by: Hugh Dickins <hughd@google.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/numa: Fix percpu allocations to be NUMA awareMichael Ellerman2017-06-061-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In commit 8c272261194d ("powerpc/numa: Enable USE_PERCPU_NUMA_NODE_ID"), we switched to the generic implementation of cpu_to_node(), which uses a percpu variable to hold the NUMA node for each CPU. Unfortunately we neglected to notice that we use cpu_to_node() in the allocation of our percpu areas, leading to a chicken and egg problem. In practice what happens is when we are setting up the percpu areas, cpu_to_node() reports that all CPUs are on node 0, so we allocate all percpu areas on node 0. This is visible in the dmesg output, as all pcpu allocs being in group 0: pcpu-alloc: [0] 00 01 02 03 [0] 04 05 06 07 pcpu-alloc: [0] 08 09 10 11 [0] 12 13 14 15 pcpu-alloc: [0] 16 17 18 19 [0] 20 21 22 23 pcpu-alloc: [0] 24 25 26 27 [0] 28 29 30 31 pcpu-alloc: [0] 32 33 34 35 [0] 36 37 38 39 pcpu-alloc: [0] 40 41 42 43 [0] 44 45 46 47 To fix it we need an early_cpu_to_node() which can run prior to percpu being setup. We already have the numa_cpu_lookup_table we can use, so just plumb it in. With the patch dmesg output shows two groups, 0 and 1: pcpu-alloc: [0] 00 01 02 03 [0] 04 05 06 07 pcpu-alloc: [0] 08 09 10 11 [0] 12 13 14 15 pcpu-alloc: [0] 16 17 18 19 [0] 20 21 22 23 pcpu-alloc: [1] 24 25 26 27 [1] 28 29 30 31 pcpu-alloc: [1] 32 33 34 35 [1] 36 37 38 39 pcpu-alloc: [1] 40 41 42 43 [1] 44 45 46 47 We can also check the data_offset in the paca of various CPUs, with the fix we see: CPU 0: data_offset = 0x0ffe8b0000 CPU 24: data_offset = 0x1ffe5b0000 And we can see from dmesg that CPU 24 has an allocation on node 1: node 0: [mem 0x0000000000000000-0x0000000fffffffff] node 1: [mem 0x0000001000000000-0x0000001fffffffff] Cc: stable@vger.kernel.org # v3.16+ Fixes: 8c272261194d ("powerpc/numa: Enable USE_PERCPU_NUMA_NODE_ID") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/kernel: Initialize load_tm on task creationBreno Leitao2017-06-061-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently tsk->thread.load_tm is not initialized in the task creation and can contain garbage on a new task. This is an undesired behaviour, since it affects the timing to enable and disable the transactional memory laziness (disabling and enabling the MSR TM bit, which affects TM reclaim and recheckpoint in the scheduling process). Fixes: 5d176f751ee3 ("powerpc: tm: Enable transactional memory (TM) lazily for userspace") Cc: stable@vger.kernel.org # v4.9+ Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/kernel: Fix FP and vector register restorationBreno Leitao2017-06-051-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently tsk->thread->load_vec and load_fp are not initialized during task creation, which can lead to garbage values in these variables (non-zero values). These variables will be checked later in restore_math() to validate if the FP and vector registers are being utilized. Since these values might be non-zero, the restore_math() will continue to save the FP and vectors even if they were never utilized by the userspace application. load_fp and load_vec counters will then overflow (they wrap at 255) and the FP and Altivec will be finally disabled, but before that condition is reached (counter overflow) several context switches will have restored FP and vector registers without need, causing a performance degradation. Fixes: 70fe3d980f5f ("powerpc: Restore FPU/VEC/VSX if previously used") Cc: stable@vger.kernel.org # v4.6+ Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Gustavo Romero <gusbromero@gmail.com> Acked-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/64: Reclaim CPU_FTR_SUBCOREMichael Ellerman2017-06-011-1/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We are running low on CPU feature bits, so we only want to use them when it's really necessary. CPU_FTR_SUBCORE is only used in one place, and only in C, so we don't need it in order to make asm patching work. It can only be set on "Power8" CPUs, which in practice means POWER8, POWER8E and POWER8NVL. There are no plans to implement it on future CPUs, but if there ever were we could retrofit it then. Although KVM uses subcores, it never looks at the CPU feature, it either looks at the ISA level or the threads_per_subcore value. So drop the CPU feature and do a PVR check instead. Drop the device tree "subcore" feature as we no longer support doing anything with it, and we will drop it from skiboot too. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | powerpc/64s: Add dt_cpu_ftrs boot time setup optionNicholas Piggin2017-06-011-9/+48
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Provide a dt_cpu_ftrs= cmdline option to disable the dt_cpu_ftrs CPU feature discovery, and fall back to the "cputable" based version. Also allow control of advertising unknown features to userspace and with this parameter, and remove the clunky CONFIG option. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Add explicit early check of bootargs in dt_cpu_ftrs_init()] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc: Add PPC_FEATURE userspace bits for SCV and DARN instructionsNicholas Piggin2017-05-251-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Providing "scv" support to userspace requires kernel support, so it must be advertised as independently to the base ISA 3 instruction set. The darn instruction relies on firmware enablement, so it has been decided to split this out from the core ISA 3 feature as well. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc: Fix booting P9 hash with CONFIG_PPC_RADIX_MMU=NMichael Neuling2017-05-251-0/+2
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently if you disable CONFIG_PPC_RADIX_MMU you'll crash on boot on a P9. This is because we still set MMU_FTR_TYPE_RADIX via ibm,pa-features and MMU_FTR_TYPE_RADIX is what's used for code patching in much of the asm code (ie. slb_miss_realmode) This patch fixes the problem by stopping MMU_FTR_TYPE_RADIX from being set from ibm.pa-features. We may eventually end up removing the CONFIG_PPC_RADIX_MMU option completely but until then this fixes the issue. Fixes: 17a3dd2f5fc7 ("powerpc/mm/radix: Use firmware feature to enable Radix MMU") Cc: stable@vger.kernel.org # v4.7+ Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>