- 04 Sep, 2017 1 commit
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Paul Mackerras authored
Commit 350779a2 ("powerpc: Handle most loads and stores in instruction emulation code", 2017-08-30) changed the register usage in get_vr and put_vr with the aim of leaving the register number in r3 untouched on return. Unfortunately, r6 was not a good choice, as the callers as of 350779a2 store a MSR value in r6. Then, in commit c22435a5 ("powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live", 2017-08-30), the saving and restoring of the MSR got moved into get_vr and put_vr. Either way, the effect is that we put a value in MSR that only has the 0x3f8 bits non-zero, meaning that we are switching to 32-bit mode. That leads to a crash like this: Unable to handle kernel paging request for instruction fetch Faulting instruction address: 0x0007bea0 Oops: Kernel access of bad area, sig: 11 [#12] LE SMP NR_CPUS=2048 NUMA PowerNV Modules linked in: vmx_crypto binfmt_misc ip_tables x_tables autofs4 crc32c_vpmsum CPU: 6 PID: 32659 Comm: trashy_testcase Tainted: G D 4.13.0-rc2-00313-gf3026f57e6ed-dirty #23 task: c000000f1bb9e780 task.stack: c000000f1ba98000 NIP: 000000000007bea0 LR: c00000000007b054 CTR: c00000000007be70 REGS: c000000f1ba9b960 TRAP: 0400 Tainted: G D (4.13.0-rc2-00313-gf3026f57e6ed-dirty) MSR: 10000000400010a1 <HV,ME,IR,LE> CR: 48000228 XER: 00000000 CFAR: c00000000007be74 SOFTE: 1 GPR00: c00000000007b054 c000000f1ba9bbe0 c000000000e6e000 000000000000001d GPR04: c000000f1ba9bc00 c00000000007be70 00000000000000e8 9000000002009033 GPR08: 0000000002000000 100000000282f033 000000000b0a0900 0000000000001009 GPR12: 0000000000000000 c00000000fd42100 0706050303020100 a5a5a5a5a5a5a5a5 GPR16: 2e2e2e2e2e2de70c 2e2e2e2e2e2e2e2d 0000000000ff00ff 0606040202020000 GPR20: 000000000000005b ffffffffffffffff 0000000003020100 0000000000000000 GPR24: c000000f1ab90020 c000000f1ba9bc00 0000000000000001 0000000000000001 GPR28: c000000f1ba9bc90 c000000f1ba9bea0 000000000b0a0908 0000000000000001 NIP [000000000007bea0] 0x7bea0 LR [c00000000007b054] emulate_loadstore+0x1044/0x1280 Call Trace: [c000000f1ba9bbe0] [c000000000076b80] analyse_instr+0x60/0x34f0 (unreliable) [c000000f1ba9bc70] [c00000000007b7ec] emulate_step+0x23c/0x544 [c000000f1ba9bce0] [c000000000053424] arch_uprobe_skip_sstep+0x24/0x40 [c000000f1ba9bd00] [c00000000024b2f8] uprobe_notify_resume+0x598/0xba0 [c000000f1ba9be00] [c00000000001c284] do_notify_resume+0xd4/0xf0 [c000000f1ba9be30] [c00000000000bd44] ret_from_except_lite+0x70/0x74 Instruction dump: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX ---[ end trace a7ae7a7f3e0256b5 ]--- To fix this, we just revert to using r3 as before, since the callers don't rely on r3 being left unmodified. Fortunately, this can't be triggered by a misaligned load or store, because vector loads and stores truncate misaligned addresses rather than taking an alignment interrupt. It can be triggered using uprobes. Fixes: 350779a2 ("powerpc: Handle most loads and stores in instruction emulation code") Reported-by: Anton Blanchard <anton@ozlabs.org> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Tested-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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- 02 Sep, 2017 8 commits
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Cédric Le Goater authored
Having the CPU identifier in the debug logs is helpful when tracking issues. Also add some more logging and fix a compile issue in xive_do_source_eoi(). Signed-off-by: Cédric Le Goater <clg@kaod.org> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Cédric Le Goater authored
On POWER9, the Client Architecture Support (CAS) negotiation process determines whether the guest operates in XIVE Legacy compatibility or in XIVE exploitation mode. Now that we have initial guest support for the XIVE interrupt controller, let's inform the hypervisor what we can do. The platform advertises the XIVE Exploitation Mode support using the property "ibm,arch-vec-5-platform-support-vec-5", byte 23 bits 0-1 : - 0b00 XIVE legacy mode Only - 0b01 XIVE exploitation mode Only - 0b10 XIVE legacy or exploitation mode The OS asks for XIVE Exploitation Mode support using the property "ibm,architecture-vec-5", byte 23 bits 0-1: - 0b00 XIVE legacy mode Only - 0b01 XIVE exploitation mode Only Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Cédric Le Goater authored
The H_INT_ESB hcall() is used to issue a load or store to the ESB page instead of using the MMIO pages. This can be used as a workaround on some HW issues. The OS knows that this hcall should be used on an interrupt source when the ESB hcall flag is set to 1 in the hcall H_INT_GET_SOURCE_INFO. To maintain the frontier between the xive frontend and backend, we introduce a new xive operation 'esb_rw' to be used in the routines doing memory accesses on the ESBs. Signed-off-by: Cédric Le Goater <clg@kaod.org> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Cédric Le Goater authored
It will be required later by the H_INT_ESB hcall. Signed-off-by: Cédric Le Goater <clg@kaod.org> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Cédric Le Goater authored
Some source support MMIO stores on the ESB page to perform EOI. Let's introduce a specific routine for this case even if this should be the only use of it. Signed-off-by: Cédric Le Goater <clg@kaod.org> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Cédric Le Goater authored
xive_poke_esb() is performing a load/read so it is better named as xive_esb_read() as we will need to introduce a xive_esb_write() routine. Also use the XIVE_ESB_LOAD_EOI offset when EOI'ing LSI interrupts. Signed-off-by: Cédric Le Goater <clg@kaod.org> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Cédric Le Goater authored
This is the framework for using XIVE in a PowerVM guest. The support is very similar to the native one in a much simpler form. Each source is associated with an Event State Buffer (ESB). This is a two bit state machine which is used to trigger events. The bits are named "P" (pending) and "Q" (queued) and can be controlled by MMIO. The Guest OS registers event (or notifications) queues on which the HW will post event data for a target to notify. Instead of OPAL calls, a set of Hypervisors call are used to configure the interrupt sources and the event/notification queues of the guest: - H_INT_GET_SOURCE_INFO used to obtain the address of the MMIO page of the Event State Buffer (PQ bits) entry associated with the source. - H_INT_SET_SOURCE_CONFIG assigns a source to a "target". - H_INT_GET_SOURCE_CONFIG determines to which "target" and "priority" is assigned to a source - H_INT_GET_QUEUE_INFO returns the address of the notification management page associated with the specified "target" and "priority". - H_INT_SET_QUEUE_CONFIG sets or resets the event queue for a given "target" and "priority". It is also used to set the notification config associated with the queue, only unconditional notification for the moment. Reset is performed with a queue size of 0 and queueing is disabled in that case. - H_INT_GET_QUEUE_CONFIG returns the queue settings for a given "target" and "priority". - H_INT_RESET resets all of the partition's interrupt exploitation structures to their initial state, losing all configuration set via the hcalls H_INT_SET_SOURCE_CONFIG and H_INT_SET_QUEUE_CONFIG. - H_INT_SYNC issue a synchronisation on a source to make sure sure all notifications have reached their queue. As for XICS, the XIVE interface for the guest is described in the device tree under the "interrupt-controller" node. A couple of new properties are specific to XIVE : - "reg" contains the base address and size of the thread interrupt managnement areas (TIMA), also called rings, for the User level and for the Guest OS level. Only the Guest OS level is taken into account today. - "ibm,xive-eq-sizes" the size of the event queues. One cell per size supported, contains log2 of size, in ascending order. - "ibm,xive-lisn-ranges" the interrupt numbers ranges assigned to the guest. These are allocated using a simple bitmap. and also : - "/ibm,plat-res-int-priorities" contains a list of priorities that the hypervisor has reserved for its own use. Tested with a QEMU XIVE model for pseries and with the Power hypervisor. Signed-off-by: Cédric Le Goater <clg@kaod.org> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Cédric Le Goater authored
This routine will be used in the spapr backend. Also introduce a short xive_alloc_order() helper. Signed-off-by: Cédric Le Goater <clg@kaod.org> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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- 01 Sep, 2017 31 commits
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Michael Ellerman authored
Older compilers think val may be used uninitialized: arch/powerpc/lib/sstep.c: In function 'emulate_loadstore': arch/powerpc/lib/sstep.c:2758:23: error: 'val' may be used uninitialized in this function We know better, but initialise val to 0 to avoid breaking the build. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Markus Elfring authored
* Return directly after a call of the function "kzalloc" failed at the beginning. * Delete a repeated check for the local variable "bank" which became unnecessary with this refactoring. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Markus Elfring authored
Replace the specification of a data structure by a pointer dereference as the parameter for the operator "sizeof" to make the corresponding size determination a bit safer according to the Linux coding style convention. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Markus Elfring authored
Omit an extra message for a memory allocation failure in this function. This issue was detected by using the Coccinelle software. Link: http://events.linuxfoundation.org/sites/events/files/slides/LCJ16-Refactor_Strings-WSang_0.pdfSigned-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Alistair Popple authored
The nest MMU tlb flush needs to happen before the GPU translation shootdown is launched to avoid the GPU refilling its tlb with stale nmmu translations prior to the nmmu flush completing. Fixes: 1ab66d1f ("powerpc/powernv: Introduce address translation services for Nvlink2") Cc: stable@vger.kernel.org # v4.12+ Signed-off-by: Alistair Popple <alistair@popple.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Julia Lawall authored
The wf_sensor_ops structures are only stored in the ops field of a wf_sensor structure, which is declared as const. Thus the wf_sensor_ops structures themselves can be const. Done with the help of Coccinelle. // <smpl> @r disable optional_qualifier@ identifier i; position p; @@ static struct wf_sensor_ops i@p = { ... }; @ok1@ identifier r.i; struct wf_sensor s; position p; @@ s.ops = &i@p @ok2@ identifier r.i; struct wf_sat_sensor s; position p; @@ s.sens.ops = &i@p @bad@ position p != {r.p,ok1.p,ok2.p}; identifier r.i; struct wf_sensor_ops e; @@ e@i@p @depends on !bad disable optional_qualifier@ identifier r.i; @@ static +const struct wf_sensor_ops i = { ... }; // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Julia Lawall authored
Use DEVICE_ATTR_RW for read-write attributes. This simplifies the source code, improves readbility, and reduces the chance of inconsistencies. Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Markus Elfring authored
Omit an extra message for a memory allocation failure in eeh_dev_init(). This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> [mpe: Do not drop the message that can happen at runtime and lead to an event not being handled] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Markus Elfring authored
Two single characters (line breaks) should be put into a sequence. Thus use the corresponding function "seq_putc". This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Rob Herring authored
Now that we have a custom printf format specifier, convert users of full_name to use %pOF instead. This is preparation to remove storing of the full path string for each node. Signed-off-by: Rob Herring <robh@kernel.org> [mpe: Also convert the two cases inside #if 0] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Rob Herring authored
Now that we have a custom printf format specifier, convert users of full_name to use %pOF instead. This is preparation to remove storing of the full path string for each node. Signed-off-by: Rob Herring <robh@kernel.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: linux-ide@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Haren Myneni authored
This patch adds P9 NX support for 842 compression engine. Virtual Accelerator Switchboard (VAS) is used to access 842 engine on P9. For each NX engine per chip, setup receive window using vas_rx_win_open() which configures RxFIFo with FIFO address, lpid, pid and tid values. This unique (lpid, pid, tid) combination will be used to identify the target engine. For crypto open request, open send window on the NX engine for the corresponding chip / cpu where the open request is executed. This send window will be closed upon crypto close request. NX provides high and normal priority FIFOs. For compression / decompression requests, we use only hight priority FIFOs in kernel. Each NX request will be communicated to VAS using copy/paste instructions with vas_copy_crb() / vas_paste_crb() functions. Signed-off-by: Haren Myneni <haren@us.ibm.com> Reviewed-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Haren Myneni authored
This patch adds changes for checking P9 specific 842 engine error codes. These errros are reported in coprocessor status block (CSB) for failures. Signed-off-by: Haren Myneni <haren@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Haren Myneni authored
Send window is opened / closed for each crypto session. So initializes txwin in workmem. Signed-off-by: Haren Myneni <haren@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Haren Myneni authored
Updating coprocessor list is moved to nx842_add_coprocs_list(). This function will be used for both icswx and VAS functions. Signed-off-by: Haren Myneni <haren@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Haren Myneni authored
Move deleting coprocessors info upon exit or failure to nx842_delete_coprocs(). Signed-off-by: Haren Myneni <haren@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Haren Myneni authored
Configure CRB is moved to nx842_configure_crb() so that it can be used for icswx and VAS exec functions. VAS function will be added later with P9 support. Signed-off-by: Haren Myneni <haren@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Haren Myneni authored
Rename nx842_powernv_function to nx842_powernv_exec. nx842_powernv_exec points to nx842_exec_icswx and will be point to VAS exec function which will be added later for P9 NX support. Signed-off-by: Haren Myneni <haren@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Christophe Leroy authored
memset() is patched after initialisation to activate the optimised part which uses cache instructions. Today we have a 'b 2f' to skip the optimised patch, which then gets replaced by a NOP, implying a useless cycle consumption. As we have a 'bne 2f' just before, we could use that instruction for the live patching, hence removing the need to have a dedicated 'b 2f' to be replaced by a NOP. This patch changes the 'bne 2f' by a 'b 2f'. During init, that 'b 2f' is then replaced by 'bne 2f' Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Christophe Leroy authored
There is no need to extend the set value to an int when the length is lower than 4 as in that case we only do byte stores. We can therefore immediately branch to the part handling it. By separating it from the normal case, we are able to eliminate a few actions on the destination pointer. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Christophe Leroy authored
Commit 9445aa1a ("ppc: move exports to definitions") added EXPORT_SYMBOL() for memset() and flush_hash_pages() in the middle of the functions. This patch moves them at the end of the two functions. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Christophe Leroy authored
Commit 694fc88c ("powerpc/string: Implement optimized memset variants") added memset16(), memset32() and memset64() for the 64 bits PPC. On 32 bits, memset64() is not relevant, and as shown below, the generic version of memset32() gives a good code, so only memset16() is candidate for an optimised version. 000009c0 <memset32>: 9c0: 2c 05 00 00 cmpwi r5,0 9c4: 39 23 ff fc addi r9,r3,-4 9c8: 4d 82 00 20 beqlr 9cc: 7c a9 03 a6 mtctr r5 9d0: 94 89 00 04 stwu r4,4(r9) 9d4: 42 00 ff fc bdnz 9d0 <memset32+0x10> 9d8: 4e 80 00 20 blr The last part of memset() handling the not 4-bytes multiples operates on bytes, making it unsuitable for handling word without modification. As it would increase memset() complexity, it is better to implement memset16() from scratch. In addition it has the advantage of allowing a more optimised memset16() than what we would have by using the memset() function. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Paul Mackerras authored
Michael Ellerman reported that emulate_loadstore() was trying to access element 32 of regs->gpr[], which doesn't exist, when emulating a string store instruction. This is because the string load and store instructions (lswi, lswx, stswi and stswx) are defined to wrap around from register 31 to register 0 if the number of bytes being loaded or stored is sufficiently large. This wrapping was not implemented in the emulation code. To fix it, we mask the register number after incrementing it. Reported-by: Michael Ellerman <mpe@ellerman.id.au> Fixes: c9f6f4ed ("powerpc: Implement emulation of string loads and stores") Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Paul Mackerras authored
This adds emulation for the lfiwax, lfiwzx and stfiwx instructions. This necessitated adding a new flag to indicate whether a floating point or an integer conversion was needed for LOAD_FP and STORE_FP, so this moves the size field in op->type up 4 bits. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Paul Mackerras authored
This replaces almost all of the instruction emulation code in fix_alignment() with calls to analyse_instr(), emulate_loadstore() and emulate_dcbz(). The only emulation code left is the SPE emulation code; analyse_instr() etc. do not handle SPE instructions at present. One result of this is that we can now handle alignment faults on all the new VSX load and store instructions that were added in POWER9. VSX loads/stores will take alignment faults for unaligned accesses to cache-inhibited memory. Another effect is that we no longer rely on the DAR and DSISR values set by the processor. With this, we now need to include the instruction emulation code unconditionally. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Paul Mackerras authored
This moves the parts of emulate_step() that deal with emulating load and store instructions into a new function called emulate_loadstore(). This is to make it possible to reuse this code in the alignment handler. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Paul Mackerras authored
This adds code to the load and store emulation code to byte-swap the data appropriately when the process being emulated is set to the opposite endianness to that of the kernel. This also enables the emulation for the multiple-register loads and stores (lmw, stmw, lswi, stswi, lswx, stswx) to work for little-endian. In little-endian mode, the partial word at the end of a transfer for lsw*/stsw* (when the byte count is not a multiple of 4) is loaded/stored at the least-significant end of the register. Additionally, this fixes a bug in the previous code in that it could call read_mem/write_mem with a byte count that was not 1, 2, 4 or 8. Note that this only works correctly on processors with "true" little-endian mode, such as IBM POWER processors from POWER6 on, not the so-called "PowerPC" little-endian mode that uses address swizzling as implemented on the old 32-bit 603, 604, 740/750, 74xx CPUs. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Paul Mackerras authored
This adds code to the instruction emulation code to set regs->dar to the address of any memory access that fails. This address is not necessarily the same as the effective address of the instruction, because if the memory access is unaligned, it might cross a page boundary and fault on the second page. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Paul Mackerras authored
This adds code to analyse_instr() and emulate_step() to understand the dcbz (data cache block zero) instruction. The emulate_dcbz() function is made public so it can be used by the alignment handler in future. (The apparently unnecessary cropping of the address to 32 bits is there because it will be needed in that situation.) Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Paul Mackerras authored
This adds lfdp[x] and stfdp[x] to the set of instructions that analyse_instr() and emulate_step() understand. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Paul Mackerras authored
This adds code to analyse_instr() and emulate_step() to handle the vector element loads and stores: lvebx, lvehx, lvewx, stvebx, stvehx, stvewx. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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