- 06 Jul, 2017 16 commits
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Gary R Hook authored
The Debug FS entries manage themselves; we don't need to hang onto them in the context structure. Signed-off-by:
Gary R Hook <gary.hook@amd.com> Acked-by:
Dave Jiang <dave.jiang@intel.com> Signed-off-by:
Jon Mason <jdmason@kudzu.us>
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Gary R Hook authored
The DMA channel(s)/memory used to transfer data to an NTB device may not be required to be on the same node as the device. Add a module parameter that allows any candidate channel (aside from node assocation) and allocated memory to be used. Signed-off-by:
Gary R Hook <gary.hook@amd.com> Acked-by:
Dave Jiang <dave.jiang@intel.com> Signed-off-by:
Jon Mason <jdmason@kudzu.us>
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Serge Semin authored
IDT 89HPESxNTx device series is PCIe-switches, which support Non-Transparent bridging between domains connected to the device ports. Since new NTB API exposes multi-port interface and messaging API, the IDT NT-functions can be now supported in the kernel. This driver adds the following functionality: 1) Multi-port NTB API to have information of possible NT-functions activated in compliance with available device ports. 2) Memory windows of direct and look up table based address translation with all possible combinations of BARs setup. 3) Traditional doorbell NTB API. 4) One-on-one messaging NTB API. There are some IDT PCIe-switch setups, which must be done before any of the NTB peers started. It can be performed either by system BIOS via IDT SMBus-slave interface or by pre-initialized IDT PCIe-switch EEPROM: 1) NT-functions of corresponding ports must be activated using SWPARTxCTL and SWPORTxCTL registers. 2) BAR0 must be configured to expose NT-function configuration registers map. 3) The rest of the BARs must have at least one memory window configured, otherwise the driver will just return an error. Temperature sensor of IDT PCIe-switches can be also optionally activated by BIOS or EEPROM. (See IDT documentations for details of how the pre-initialization can be done) Signed-off-by:
Serge Semin <fancer.lancer@gmail.com> Acked-by:
Allen Hubbe <Allen.Hubbe@dell.com> Signed-off-by:
Jon Mason <jdmason@kudzu.us>
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Logan Gunthorpe authored
As per a comments in [1] by Greg Kroah-Hartman, the ndev_* macros should be cleaned up. This makes it more clear what's actually going on when reading the code. [1] http://www.spinics.net/lists/linux-pci/msg56904.htmlSigned-off-by:
Logan Gunthorpe <logang@deltatee.com> Signed-off-by:
Jon Mason <jdmason@kudzu.us>
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Logan Gunthorpe authored
As per a comments in [1] by Greg Kroah-Hartman, the ndev_* macros should be cleaned up. This makes it more clear what's actually going on when reading the code. [1] http://www.spinics.net/lists/linux-pci/msg56904.htmlSigned-off-by:
Logan Gunthorpe <logang@deltatee.com> Signed-off-by:
Jon Mason <jdmason@kudzu.us>
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Serge Semin authored
Signed-off-by:
Serge Semin <fancer.lancer@gmail.com> Acked-by:
Allen Hubbe <Allen.Hubbe@dell.com> Signed-off-by:
Jon Mason <jdmason@kudzu.us>
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Serge Semin authored
Signed-off-by:
Serge Semin <fancer.lancer@gmail.com> Acked-by:
Allen Hubbe <Allen.Hubbe@dell.com> Signed-off-by:
Jon Mason <jdmason@kudzu.us>
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Serge Semin authored
Since the new API slightly changes the way a typical NTB client driver works, the documentation file needs to be appropriately updated. Signed-off-by:
Serge Semin <fancer.lancer@gmail.com> Acked-by:
Allen Hubbe <Allen.Hubbe@dell.com> Signed-off-by:
Jon Mason <jdmason@kudzu.us>
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Serge Semin authored
Some IDT NTB-capable PCIe-switches have message registers to communicate with peer devices. This patch adds new NTB API callback methods, which can be used to utilize these registers functionality: ntb_msg_count(); - get number of message registers ntb_msg_inbits(); - get bitfield of inbound message registers status ntb_msg_outbits(); - get bitfield of outbound message registers status ntb_msg_read_sts(); - read the inbound and outbound message registers status ntb_msg_clear_sts(); - clear status bits of message registers ntb_msg_set_mask(); - mask interrupts raised by status bits of message registers. ntb_msg_clear_mask(); - clear interrupts mask bits of message registers ntb_msg_read(midx, *pidx); - read message register with specified index, additionally getting peer port index which data received from ntb_msg_write(midx, pidx); - write data to the specified message register sending it to the passed peer device connected over a pidx port ntb_msg_event(); - notify driver context of a new message event Of course there is hardware which doesn't support Message registers, so this API is made optional. Signed-off-by:
Serge Semin <fancer.lancer@gmail.com> Acked-by:
Allen Hubbe <Allen.Hubbe@dell.com> Signed-off-by:
Jon Mason <jdmason@kudzu.us>
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Serge Semin authored
Even though there is no any real NTB hardware, which would have both more than two ports and Scratchpad registers, it is logically correct to have Scratchpad API accepting a peer port index as well. Intel/AMD drivers utilize Primary and Secondary topology to split Scratchpad between connected root devices. Since port-index API introduced, Intel/AMD NTB hardware drivers can use device port to determine which Scratchpad registers actually belong to local and peer devices. The same approach can be used if some potential hardware in future will be multi-port and have some set of Scratchpads. Here are the brief of changes in the API: ntb_spad_count() - return number of Scratchpads per each port ntb_peer_spad_addr(pidx, sidx) - address of Scratchpad register of the peer device with pidx-index ntb_peer_spad_read(pidx, sidx) - read specified Scratchpad register of the peer with pidx-index ntb_peer_spad_write(pidx, sidx) - write data to Scratchpad register of the peer with pidx-index Since there is hardware which doesn't support Scratchpad registers, the corresponding API methods are now made optional. Signed-off-by:
Serge Semin <fancer.lancer@gmail.com> Acked-by:
Allen Hubbe <Allen.Hubbe@dell.com> Signed-off-by:
Jon Mason <jdmason@kudzu.us>
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Serge Semin authored
Multi-port NTB devices permit to share a memory between all accessible peers. Memory Windows API is altered to correspondingly initialize and map memory windows for such devices: ntb_mw_count(pidx); - number of inbound memory windows, which can be allocated for shared buffer with specified peer device. ntb_mw_get_align(pidx, widx); - get alignment and size restriction parameters to properly allocate inbound memory region. ntb_peer_mw_count(); - get number of outbound memory windows. ntb_peer_mw_get_addr(widx); - get mapping address of an outbound memory window If hardware supports inbound translation configured on the local ntb port: ntb_mw_set_trans(pidx, widx); - set translation address of allocated inbound memory window so a peer device could access it. ntb_mw_clear_trans(pidx, widx); - clear the translation address of an inbound memory window. If hardware supports outbound translation configured on the peer ntb port: ntb_peer_mw_set_trans(pidx, widx); - set translation address of a memory window retrieved from a peer device ntb_peer_mw_clear_trans(pidx, widx); - clear the translation address of an outbound memory window Signed-off-by:
Serge Semin <fancer.lancer@gmail.com> Acked-by:
Allen Hubbe <Allen.Hubbe@dell.com> Signed-off-by:
Jon Mason <jdmason@kudzu.us>
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Serge Semin authored
Multi-port devices permit the NTB connections between multiple domains, so a local device can have NTB link being up with one peer and being down with another. NTB link-state API is appropriately altered to return a bitfield of the link-states between the local device and possible peers. Signed-off-by:
Serge Semin <fancer.lancer@gmail.com> Acked-by:
Allen Hubbe <Allen.Hubbe@dell.com> Signed-off-by:
Jon Mason <jdmason@kudzu.us>
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Serge Semin authored
There is some NTB hardware, which can combine more than just two domains over NTB. For instance, some IDT PCIe-switches can have NTB-functions activated on more than two-ports. The different domains are distinguished by ports they are connected to. So the new port-related methods are added to the NTB API: ntb_port_number() - return local port ntb_peer_port_count() - return number of peers local port can connect to ntb_peer_port_number(pdix) - return port number by it index ntb_peer_port_idx(port) - return port index by it number Current test-drivers aren't changed much. They still support two-ports devices for the time being while multi-ports hardware drivers aren't added. By default port-related API is declared for two-ports hardware. So corresponding hardware drivers won't need to implement it. Signed-off-by:
Serge Semin <fancer.lancer@gmail.com> Signed-off-by:
Jon Mason <jdmason@kudzu.us>
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Serge Semin authored
Since link operations are usually performed before memory window access operations, it's logically better to declare link-related API before any of MW/Doorbell/Scratchpad methods. Signed-off-by:
Serge Semin <fancer.lancer@gmail.com> Signed-off-by:
Jon Mason <jdmason@kudzu.us>
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Allen Hubbe authored
If the test attempts to clear doorbell bits that are invalid for the hardware, then the test will fail. Provide a parameter to specify the doorbell bits to clear. Set default doorbell bits that work for XEON. Signed-off-by:
Allen Hubbe <Allen.Hubbe@dell.com> Acked-by:
Logan Gunthorpe <logang@deltatee.com> Signed-off-by:
Jon Mason <jdmason@kudzu.us>
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Allen Hubbe authored
Signed-off-by:
Allen Hubbe <Allen.Hubbe@dell.com> Acked-by:
Logan Gunthorpe <logang@deltatee.com> Signed-off-by:
Jon Mason <jdmason@kudzu.us>
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- 02 Jul, 2017 4 commits
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Linus Torvalds authored
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Sylvain 'ythier' Hitier authored
Signed-off-by:
Sylvain 'ythier' Hitier <sylvain.hitier@gmail.com> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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git://git.linux-mips.org/pub/scm/ralf/upstream-linusLinus Torvalds authored
Pull MIPS fixes from Ralf Baechle: "Here's a final round of fixes for 4.12: - Fix misordered instructions in assembly code making kenel startup via UHB unreliable. - Fix special case of MADDF and MADDF emulation. - Fix alignment issue in address calculation in pm-cps on 64 bit. - Fix IRQ tracing & lockdep when rescheduling - Systems with MAARs require post-DMA cache flushes. The reordering fix and the MADDF/MSUBF fix have sat in linux-next for a number of days. The others haven't propagated from my pull tree to linux-next yet but all have survived manual testing and Imagination's automated test system and there are no pending bug reports" * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: MIPS: Avoid accidental raw backtrace MIPS: Perform post-DMA cache flushes on systems with MAARs MIPS: Fix IRQ tracing & lockdep when rescheduling MIPS: pm-cps: Drop manual cache-line alignment of ready_count MIPS: math-emu: Handle zero accumulator case in MADDF and MSUBF separately MIPS: head: Reorder instructions missing a delay slot
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git://git.armlinux.org.uk/~rmk/linux-armLinus Torvalds authored
Pull ARM fix from Russell King: "One final fix for 4.12 - Doug found a boot failure case triggered by requesting a non-even MB vmalloc size" * 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm: ARM: 8685/1: ensure memblock-limit is pmd-aligned
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- 01 Jul, 2017 5 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull x86 fixes from Thomas Gleixner: "Fixlets for x86: - Prevent kexec crash when KASLR is enabled, which was caused by an address calculation bug - Restore the freeing of PUDs on memory hot remove - Correct a negated pointer check in the intel uncore performance monitoring driver - Plug a memory leak in an error exit path in the RDT code" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/intel_rdt: Fix memory leak on mount failure x86/boot/KASLR: Fix kexec crash due to 'virt_addr' calculation bug x86/boot/KASLR: Add checking for the offset of kernel virtual address randomization perf/x86/intel/uncore: Fix wrong box pointer check x86/mm/hotplug: Fix BUG_ON() after hot-remove by not freeing PUD
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull perf fix from Thomas Gleixner: "The last fix for perf for this cycles: - Prevent a segfault when kernel.kptr_restrict=2 is set by avoiding a null pointer dereference" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf machine: Fix segfault for kernel.kptr_restrict=2
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git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlLinus Torvalds authored
Pull pinctrl fix from Linus Walleij: "Brian noticed that this regression has not got a proper fix for the entire merge window and consequently we need to revert the offending commit. It's part of the RT-mainstream work, the dance goes like this, two steps forward, one step back. Summary: - A last fix for v4.12, an IRQ problem reported early in the merge window appears not to have been properly fixed, so the offending commit will be reverted and we will find the proper fix for v4.13. Hopefully" * tag 'pinctrl-v4.12-4' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: Revert "pinctrl: rockchip: avoid hardirq-unsafe functions in irq_chip"
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git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpioLinus Torvalds authored
Pull last minute fixes for GPIO from Linus Walleij: - Fix another ACPI problem with broken BIOSes. - Filter out the right GPIO events, making a very user-visible bug go away. * tag 'gpio-v4.12-4' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: gpio: acpi: Skip _AEI entries without a handler rather then aborting the scan gpiolib: fix filtering out unwanted events
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git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-traceLinus Torvalds authored
Pull last-minute tracing fixes from Steven Rostedt: "Two fixes: One is for a crash when using the :mod: trace probe command into stack_trace_filter. This bug was introduced during the last merge window. The other was there forever. It's a small bug that makes it impossible to name a module function for kprobes when the module starts with a digit" * tag 'trace-v4.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing/kprobes: Allow to create probe with a module name starting with a digit ftrace: Fix regression with module command in stack_trace_filter
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- 30 Jun, 2017 14 commits
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Zack Weinberg authored
uapi/linux/a.out.h uses a number of predefined macros that are deprecated because they're in the application namespace (e.g. '#ifdef linux' instead of '#ifdef __linux__'). This patch either corrects or just removes them if they are not applicable to Linux. The primary reason this is worth bothering to fix, considering how obsolete a.out binary support is, is that the GCC build process considers this such a severe error that it will copy the header into a private directory and change the macro names, which causes future updates to the header to be masked. This header probably doesn't get updated very often anymore, but it is the _only_ uapi header that gets this treatment, so IMHO it is worth patching just to drive that number all the way to zero. Signed-off-by:
Zack Weinberg <zackw@panix.com> [hch: removed dead conditionals] Signed-off-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Jakub Kicinski authored
"in a rcu enabled hashtable" is repeated twice in a comment. Signed-off-by:
Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Vikas Shivappa authored
If mount fails, the kn_info directory is not freed causing memory leak. Add the missing error handling path. Fixes: 4e978d06 ("x86/intel_rdt: Add "info" files to resctrl file system") Signed-off-by:
Vikas Shivappa <vikas.shivappa@linux.intel.com> Signed-off-by:
Thomas Gleixner <tglx@linutronix.de> Cc: ravi.v.shankar@intel.com Cc: tony.luck@intel.com Cc: fenghua.yu@intel.com Cc: peterz@infradead.org Cc: vikas.shivappa@intel.com Cc: andi.kleen@intel.com Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1498503368-20173-3-git-send-email-vikas.shivappa@linux.intel.com
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git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linuxLinus Torvalds authored
Pull powerpc fixes from Michael Ellerman: "Hopefully the last two powerpc fixes for 4.12. The CXL one is larger than I'd usually send at rc7, but it fixes new code this cycle, so better to have it working for the release. It was actually sent a few weeks back but got blocked in testing behind another fix that was causing issues. We are still tracking one crash in v4.12-rc7, but only one person has reproduced it and the commit identified by bisect doesn't touch any of the relevant code, so I think it's 50/50 whether that commit is actually the problem or it's some code layout / toolchain issue. Two fixes for code we merged this cycle: - cxl: Fixes for Coherent Accelerator Interface Architecture 2.0 - Avoid miscompilation w/GCC 4.6.3 on 32-bit - don't inline copy_to/from_user() Thanks to Al Viro, Larry Finger, Christophe Lombard" * tag 'powerpc-4.12-8' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/32: Avoid miscompilation w/GCC 4.6.3 - don't inline copy_to/from_user() cxl: Fixes for Coherent Accelerator Interface Architecture 2.0
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git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommuLinus Torvalds authored
Pull IOMMU fixes from Joerg Roedel: "Two fixes: - A fix for AMD IOMMU interrupt remapping code when IRQs are forwarded directly to KVM guests - Fixed check in the recently merged code to allow tboot with Intel VT-d disabled" * tag 'iommu-fixes-v4.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: iommu/amd: Fix interrupt remapping when disable guest_mode iommu/vt-d: Correctly disable Intel IOMMU force on
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git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/soundLinus Torvalds authored
Pull sound fixes from Takashi Iwai: "Two last-minute HD-audio fixes" * tag 'sound-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: ALSA: hda - Fix endless loop of codec configure ALSA: hda - set input_path bitmap to zero after moving it to new place
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git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfsLinus Torvalds authored
Pull overlayfs fixes from Miklos Szeredi: "Fix two bugs in copy-up code. One introduced in 4.11 and one in 4.12-rc" * 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: ovl: don't set origin on broken lower hardlink ovl: copy-up: don't unlock between lookup and link
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Baoquan He authored
Kernel text KASLR is separated into physical address and virtual address randomization. And for virtual address randomization, we only randomiza to get an offset between 16M and KERNEL_IMAGE_SIZE. So the initial value of 'virt_addr' should be LOAD_PHYSICAL_ADDR, but not the original kernel loading address 'output'. The bug will cause kernel boot failure if kernel is loaded at a different position than the address, 16M, which is decided at compiled time. Kexec/kdump is such practical case. To fix it, just assign LOAD_PHYSICAL_ADDR to virt_addr as initial value. Tested-by:
Dave Young <dyoung@redhat.com> Signed-off-by:
Baoquan He <bhe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 8391c73c ("x86/KASLR: Randomize virtual address separately") Link: http://lkml.kernel.org/r/1498567146-11990-3-git-send-email-bhe@redhat.comSigned-off-by:
Ingo Molnar <mingo@kernel.org>
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Baoquan He authored
For kernel text KASLR, the virtual address is confined to area of 1G, [0xffffffff80000000, 0xffffffffc0000000). For the implemenataion of virtual address randomization, we only randomize to get an offset between 16M and 1G, then add this offset to the starting address, 0xffffffff80000000. Here 16M is the offset which is decided at linking stage. So the amount of the local variable 'virt_addr' which respresents the offset plus the kernel output size can not exceed KERNEL_IMAGE_SIZE. Add a debug check for the offset. If out of bounds, print error message and hang there. Suggested-by:
Ingo Molnar <mingo@kernel.org> Signed-off-by:
Baoquan He <bhe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1498567146-11990-2-git-send-email-bhe@redhat.comSigned-off-by:
Ingo Molnar <mingo@kernel.org>
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Sabrina Dubroca authored
Always try to parse an address, since kstrtoul() will safely fail when given a symbol as input. If that fails (which will be the case for a symbol), try to parse a symbol instead. This allows creating a probe such as: p:probe/vlan_gro_receive 8021q:vlan_gro_receive+0 Which is necessary for this command to work: perf probe -m 8021q -a vlan_gro_receive Link: http://lkml.kernel.org/r/fd72d666f45b114e2c5b9cf7e27b91de1ec966f1.1498122881.git.sd@queasysnail.net Cc: stable@vger.kernel.org Fixes: 413d37d1 ("tracing: Add kprobe-based event tracer") Acked-by:
Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by:
Sabrina Dubroca <sd@queasysnail.net> Signed-off-by:
Steven Rostedt (VMware) <rostedt@goodmis.org>
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James Hogan authored
Since commit 81a76d71 ("MIPS: Avoid using unwind_stack() with usermode") show_backtrace() invokes the raw backtracer when cp0_status & ST0_KSU indicates user mode to fix issues on EVA kernels where user and kernel address spaces overlap. However this is used by show_stack() which creates its own pt_regs on the stack and leaves cp0_status uninitialised in most of the code paths. This results in the non deterministic use of the raw back tracer depending on the previous stack content. show_stack() deals exclusively with kernel mode stacks anyway, so explicitly initialise regs.cp0_status to KSU_KERNEL (i.e. 0) to ensure we get a useful backtrace. Fixes: 81a76d71 ("MIPS: Avoid using unwind_stack() with usermode") Signed-off-by:
James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Cc: <stable@vger.kernel.org> # 3.15+ Patchwork: https://patchwork.linux-mips.org/patch/16656/Signed-off-by:
Ralf Baechle <ralf@linux-mips.org>
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Paul Burton authored
Recent CPUs from Imagination Technologies such as the I6400 or P6600 are able to speculatively fetch data from memory into caches. This means that if used in a system with non-coherent DMA they require that caches be invalidated after a device performs DMA, and before the CPU reads the DMA'd data, in order to ensure that stale values weren't speculatively prefetched. Such CPUs also introduced Memory Accessibility Attribute Registers (MAARs) in order to control the regions in which they are allowed to speculate. Thus we can use the presence of MAARs as a good indication that the CPU requires the above cache maintenance. Use the presence of MAARs to determine the result of cpu_needs_post_dma_flush() in the default case, in order to handle these recent CPUs correctly. Note that the return type of cpu_needs_post_dma_flush() is changed to bool, such that it's clearer what's happening when cpu_has_maar is cast to bool for the return value. If this patch were backported to a pre-v4.7 kernel then MIPS_CPU_MAAR was 1ull<<34, so when cast to an int we would incorrectly return 0. It so happens that MIPS_CPU_MAAR is currently 1ull<<30, so when truncated to an int gives a non-zero value anyway, but even so the implicit conversion from long long int to bool makes it clearer to understand what will happen than the implicit conversion from long long int to int would. The bool return type also fits this usage better semantically, so seems like an all-round win. Thanks to Ed for spotting the issue for pre-v4.7 kernels & suggesting the return type change. Signed-off-by:
Paul Burton <paul.burton@imgtec.com> Reviewed-by:
Bryan O'Donoghue <pure.logic@nexus-software.ie> Tested-by:
Bryan O'Donoghue <pure.logic@nexus-software.ie> Cc: Ed Blake <ed.blake@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16363/Signed-off-by:
Ralf Baechle <ralf@linux-mips.org>
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Paul Burton authored
When the scheduler sets TIF_NEED_RESCHED & we call into the scheduler from arch/mips/kernel/entry.S we disable interrupts. This is true regardless of whether we reach work_resched from syscall_exit_work, resume_userspace or by looping after calling schedule(). Although we disable interrupts in these paths we don't call trace_hardirqs_off() before calling into C code which may acquire locks, and we therefore leave lockdep with an inconsistent view of whether interrupts are disabled or not when CONFIG_PROVE_LOCKING & CONFIG_DEBUG_LOCKDEP are both enabled. Without tracing this interrupt state lockdep will print warnings such as the following once a task returns from a syscall via syscall_exit_partial with TIF_NEED_RESCHED set: [ 49.927678] ------------[ cut here ]------------ [ 49.934445] WARNING: CPU: 0 PID: 1 at kernel/locking/lockdep.c:3687 check_flags.part.41+0x1dc/0x1e8 [ 49.946031] DEBUG_LOCKS_WARN_ON(current->hardirqs_enabled) [ 49.946355] CPU: 0 PID: 1 Comm: init Not tainted 4.10.0-00439-gc9fd5d362289-dirty #197 [ 49.963505] Stack : 0000000000000000 ffffffff81bb5d6a 0000000000000006 ffffffff801ce9c4 [ 49.974431] 0000000000000000 0000000000000000 0000000000000000 000000000000004a [ 49.985300] ffffffff80b7e487 ffffffff80a24498 a8000000ff160000 ffffffff80ede8b8 [ 49.996194] 0000000000000001 0000000000000000 0000000000000000 0000000077c8030c [ 50.007063] 000000007fd8a510 ffffffff801cd45c 0000000000000000 a8000000ff127c88 [ 50.017945] 0000000000000000 ffffffff801cf928 0000000000000001 ffffffff80a24498 [ 50.028827] 0000000000000000 0000000000000001 0000000000000000 0000000000000000 [ 50.039688] 0000000000000000 a8000000ff127bd0 0000000000000000 ffffffff805509bc [ 50.050575] 00000000140084e0 0000000000000000 0000000000000000 0000000000040a00 [ 50.061448] 0000000000000000 ffffffff8010e1b0 0000000000000000 ffffffff805509bc [ 50.072327] ... [ 50.076087] Call Trace: [ 50.079869] [<ffffffff8010e1b0>] show_stack+0x80/0xa8 [ 50.086577] [<ffffffff805509bc>] dump_stack+0x10c/0x190 [ 50.093498] [<ffffffff8015dde0>] __warn+0xf0/0x108 [ 50.099889] [<ffffffff8015de34>] warn_slowpath_fmt+0x3c/0x48 [ 50.107241] [<ffffffff801c15b4>] check_flags.part.41+0x1dc/0x1e8 [ 50.114961] [<ffffffff801c239c>] lock_is_held_type+0x8c/0xb0 [ 50.122291] [<ffffffff809461b8>] __schedule+0x8c0/0x10f8 [ 50.129221] [<ffffffff80946a60>] schedule+0x30/0x98 [ 50.135659] [<ffffffff80106278>] work_resched+0x8/0x34 [ 50.142397] ---[ end trace 0cb4f6ef5b99fe21 ]--- [ 50.148405] possible reason: unannotated irqs-off. [ 50.154600] irq event stamp: 400463 [ 50.159566] hardirqs last enabled at (400463): [<ffffffff8094edc8>] _raw_spin_unlock_irqrestore+0x40/0xa8 [ 50.171981] hardirqs last disabled at (400462): [<ffffffff8094eb98>] _raw_spin_lock_irqsave+0x30/0xb0 [ 50.183897] softirqs last enabled at (400450): [<ffffffff8016580c>] __do_softirq+0x4ac/0x6a8 [ 50.195015] softirqs last disabled at (400425): [<ffffffff80165e78>] irq_exit+0x110/0x128 Fix this by using the TRACE_IRQS_OFF macro to call trace_hardirqs_off() when CONFIG_TRACE_IRQFLAGS is enabled. This is done before invoking schedule() following the work_resched label because: 1) Interrupts are disabled regardless of the path we take to reach work_resched() & schedule(). 2) Performing the tracing here avoids the need to do it in paths which disable interrupts but don't call out to C code before hitting a path which uses the RESTORE_SOME macro that will call trace_hardirqs_on() or trace_hardirqs_off() as appropriate. We call trace_hardirqs_on() using the TRACE_IRQS_ON macro before calling syscall_trace_leave() for similar reasons, ensuring that lockdep has a consistent view of state after we re-enable interrupts. Signed-off-by:
Paul Burton <paul.burton@imgtec.com> Fixes: 1da177e4 ("Linux-2.6.12-rc2") Cc: linux-mips@linux-mips.org Cc: stable <stable@vger.kernel.org> Patchwork: https://patchwork.linux-mips.org/patch/15385/Signed-off-by:
Ralf Baechle <ralf@linux-mips.org>
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Paul Burton authored
We allocate memory for a ready_count variable per-CPU, which is accessed via a cached non-coherent TLB mapping to perform synchronisation between threads within the core using LL/SC instructions. In order to ensure that the variable is contained within its own data cache line we allocate 2 lines worth of memory & align the resulting pointer to a line boundary. This is however unnecessary, since kmalloc is guaranteed to return memory which is at least cache-line aligned (see ARCH_DMA_MINALIGN). Stop the redundant manual alignment. Besides cleaning up the code & avoiding needless work, this has the side effect of avoiding an arithmetic error found by Bryan on 64 bit systems due to the 32 bit size of the former dlinesz. This led the ready_count variable to have its upper 32b cleared erroneously for MIPS64 kernels, causing problems when ready_count was later used on MIPS64 via cpuidle. Signed-off-by:
Paul Burton <paul.burton@imgtec.com> Fixes: 3179d37e ("MIPS: pm-cps: add PM state entry code for CPS systems") Reported-by:
Bryan O'Donoghue <bryan.odonoghue@imgtec.com> Reviewed-by:
Bryan O'Donoghue <bryan.odonoghue@imgtec.com> Tested-by:
Bryan O'Donoghue <bryan.odonoghue@imgtec.com> Cc: linux-mips@linux-mips.org Cc: stable <stable@vger.kernel.org> # v3.16+ Patchwork: https://patchwork.linux-mips.org/patch/15383/Signed-off-by:
Ralf Baechle <ralf@linux-mips.org>
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- 29 Jun, 2017 1 commit
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Doug Berger authored
The pmd containing memblock_limit is cleared by prepare_page_table() which creates the opportunity for early_alloc() to allocate unmapped memory if memblock_limit is not pmd aligned causing a boot-time hang. Commit 965278dc ("ARM: 8356/1: mm: handle non-pmd-aligned end of RAM") attempted to resolve this problem, but there is a path through the adjust_lowmem_bounds() routine where if all memory regions start and end on pmd-aligned addresses the memblock_limit will be set to arm_lowmem_limit. Since arm_lowmem_limit can be affected by the vmalloc early parameter, the value of arm_lowmem_limit may not be pmd-aligned. This commit corrects this oversight such that memblock_limit is always rounded down to pmd-alignment. Fixes: 965278dc ("ARM: 8356/1: mm: handle non-pmd-aligned end of RAM") Signed-off-by:
Doug Berger <opendmb@gmail.com> Suggested-by:
Mark Rutland <mark.rutland@arm.com> Signed-off-by:
Russell King <rmk+kernel@armlinux.org.uk>
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