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2019-08-30powerpc/64s/exception: move interrupt entry code above the common handlerNicholas Piggin
This better reflects the order in which the code is executed. No generated code change except BUG line number constants. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-34-npiggin@gmail.com
2019-08-30powerpc/64s/exception: INT_COMMON add DAR, DSISR, reconcile optionsNicholas Piggin
Move DAR and DSISR saving to pt_regs into INT_COMMON. Also add an option to expand RECONCILE_IRQ_STATE. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-33-npiggin@gmail.com
2019-08-30powerpc/64s/exception: Expand EXCEPTION_PROLOG_COMMON_1 and 2 into callerNicholas Piggin
No generated code change except BUG line number constants. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-32-npiggin@gmail.com
2019-08-30powerpc/64s/exception: Expand EXCEPTION_COMMON macro into callerNicholas Piggin
No generated code change except BUG line number constants. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-31-npiggin@gmail.com
2019-08-30powerpc/64s/exception: Add INT_COMMON gas macro to generate common exception ↵Nicholas Piggin
code No generated code change except BUG line number constants. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-30-npiggin@gmail.com
2019-08-30powerpc/64s/exception: Merge EXCEPTION_PROLOG_COMMON_2/3Nicholas Piggin
Merge EXCEPTION_PROLOG_COMMON_3 into EXCEPTION_PROLOG_COMMON_2. No generated code change except BUG line number constants. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-29-npiggin@gmail.com
2019-08-30powerpc/64s/exception: KVM_HANDLER reorder arguments to match other macrosNicholas Piggin
Also change argument name (n -> vec) to match others. No generated code change. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-28-npiggin@gmail.com
2019-08-30powerpc/64s/exception: Add INT_KVM_HANDLER gas macroNicholas Piggin
Replace the 4 variants of cpp macros with one gas macro. No generated code change except BUG line number constants. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-27-npiggin@gmail.com
2019-08-30powerpc/64s/exception: INT_HANDLER support HDAR/HDSISR and use it in HDSINicholas Piggin
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-26-npiggin@gmail.com
2019-08-30powerpc/64s/exception: Add the virt variant of the denorm interrupt handlerNicholas Piggin
All other virt handlers have the prolog code in the virt vector rather than branch to the real vector. Follow this pattern in the denorm virt handler. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-25-npiggin@gmail.com
2019-08-30powerpc/64s/exception: remove EXCEPTION_PROLOG_0/1, rename _2Nicholas Piggin
EXCEPTION_PROLOG_0 and _1 have only a single caller, so expand them into it. Rename EXCEPTION_PROLOG_2_REAL to INT_SAVE_SRR_AND_JUMP and EXCEPTION_PROLOG_2_VIRT to INT_VIRT_SAVE_SRR_AND_JUMP, which are more descriptive. No generated code change except BUG line number constants. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-24-npiggin@gmail.com
2019-08-30powerpc/64s/exceptions: Use keyword params to shorten arg listsMichael Ellerman
The argument lists for the INT_HANDLER macro are getting a bit unwieldy. Use keyword parameters with default values to shorten them. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190830011426.16810-1-mpe@ellerman.id.au
2019-08-30powerpc/64s/exception: Replace PROLOG macros and EXC helpers with a gas macroNicholas Piggin
This creates a single macro that generates the exception prolog code, with variants specified by arguments, rather than assorted nested macros for different variants. The increasing length of macro argument list is not nice to read or modify, but this is a temporary condition that will be improved in later changes. No generated code change except BUG line number constants and label names. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-23-npiggin@gmail.com
2019-08-30powerpc/64s/exception: remove 0xb00 handlerNicholas Piggin
This vector is not used by any supported processor, and has been implemented as an unknown exception going back to 2.6. There is nothing special about 0xb00, so remove it like other unused vectors. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-22-npiggin@gmail.com
2019-08-30powerpc/64s/exception: Fix performance monitor virt handlerNicholas Piggin
The perf virt handler uses EXCEPTION_PROLOG_2_REAL rather than _VIRT. In practice this is okay because the _REAL variant is usable by virt mode interrupts, but should be fixed (and is a performance win). Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-21-npiggin@gmail.com
2019-08-30powerpc/64s/exception: Add EXC_HV_OR_STD, which selects HSRR if HVMODENicholas Piggin
Add EXC_HV_OR_STD and use it to consolidate the 0x500 external interrupt. Executed code is unchanged. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-20-npiggin@gmail.com
2019-08-30powerpc/64s/exception: move head-64.h exception code to exception-64s.SNicholas Piggin
The head-64.h code should deal only with the head code sections and offset calculations. No generated code change except BUG line number constants. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-19-npiggin@gmail.com
2019-08-30powerpc/64s/exception: Fix DAR load for handle_page_fault error caseNicholas Piggin
This buglet goes back to before the 64/32 arch merge, but it does not seem to have had practical consequences because bad_page_fault does not use the 2nd argument, but rather regs->dar/nip. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-18-npiggin@gmail.com
2019-08-30powerpc/64s/exception: machine check improve labels and commentsNicholas Piggin
Short forward and backward branches can be given number labels, but larger significant divergences in code path a more readable if they're given descriptive names. Also adjusts a comment to account for guest delivery. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-17-npiggin@gmail.com
2019-08-30powerpc/64s/exception: untangle early machine check handler branchNicholas Piggin
machine_check_early_common now branches to machine_check_handle_early which is its only caller. Move interleaving code out of the way, and remove the branch. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-16-npiggin@gmail.com
2019-08-30powerpc/64s/exception: machine check move unrecoverable handling out of lineNicholas Piggin
Similarly to the previous change, all callers of the unrecoverable handler run relocated so can reach it with a direct branch. This makes it easy to move out of line, which makes the "normal" path less cluttered and easier to follow. MSR[ME] manipulation still requires the rfi, so that is moved out of line to its own function. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-15-npiggin@gmail.com
2019-08-30powerpc/64s/exception: simplify machine check early pathNicholas Piggin
machine_check_handle_early_common can reach machine_check_handle_early directly now that it runs at the relocated address, so just branch directly. The rfi sequence is required to enable MSR[ME] but that step is moved into a helper function, making the code easier to follow. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-14-npiggin@gmail.com
2019-08-30powerpc/64s/exception: machine check move tramp codeNicholas Piggin
Following convention, move the tramp code (unrelocated) above the common handlers (relocated). Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-13-npiggin@gmail.com
2019-08-30powerpc/64s/exception: machine check restructure to reuse common macrosNicholas Piggin
Follow the pattern of sreset and HMI handlers more closely: use EXCEPTION_PROLOG_COMMON_1 rather than open-coding it, and run the handler at the relocated location. This helps later simplification and code sharing. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-12-npiggin@gmail.com
2019-08-30powerpc/64s/exception: machine check pseries should skip the late handler ↵Nicholas Piggin
for kernel MCEs The powernv machine check handler copes with taking a MCE from one of three contexts, guest, kernel, and user. In each case the early handler runs first on a special stack, then: - The guest case branches to the KVM interrupt handler (via standard interrupt macros). - The user case will run the "late" handler which is like a normal interrupt that runs in virtual mode and uses the regular kernel stack. - The kernel case queues the event and schedules it for processing with irq work. The last case is important, it must not enable virtual memory because the MMU state may not be set up to deal with that (e.g., SLB might be clear), it must not use the regular kernel stack for similar reasons (e.g., might be in OPAL with OPAL stack in r1), and the kernel does not expect anything to touch its stack if interrupts are disabled. The pseries handler does not do this queueing, but instead it always runs the late handler for host MCEs, which has some of the same problems. Now that pseries is using machine_check_events, change it to do the same as powernv and queue events for kernel MCEs. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-11-npiggin@gmail.com
2019-08-30powerpc/64s/pseries: machine check convert to use common event codeNicholas Piggin
The common machine_check_event data structures and queues are mostly platform independent, with powernv decoding SRR1/DSISR/etc., into machine_check_event objects. This patch converts pseries to use this infrastructure by decoding fwnmi/rtas data into machine_check_event objects. This allows queueing to be used by a subsequent change to delay the virtual mode handling of machine checks that occur in kernel space where it is unsafe to switch immediately to virtual mode, similarly to powernv. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Fix implicit fallthrough warnings in mce_handle_error()] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-10-npiggin@gmail.com
2019-08-30powerpc/64s/powernv: machine check dump SLB contentsNicholas Piggin
Re-use the code introduced in pseries to save and dump the contents of the SLB in the case of an SLB involved machine check exception. This patch also avoids allocating the SLB save array on pseries radix. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-9-npiggin@gmail.com
2019-08-30powerpc/64s/exception: machine check use correct cfar for late handlerNicholas Piggin
Bare metal machine checks run an "early" handler in real mode before running the main handler which reports the event. The main handler runs exactly as a normal interrupt handler, after the "windup" which sets registers back as they were at interrupt entry. CFAR does not get restored by the windup code, so that will be wrong when the handler is run. Restore the CFAR to the saved value before running the late handler. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-8-npiggin@gmail.com
2019-08-30powerpc/64s/exception: machine check remove machine_check_pSeries_0 branchNicholas Piggin
This label has only one caller, so unwind the branch and move it inline. The location of the comment is adjusted to match similar one in system reset. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-7-npiggin@gmail.com
2019-08-30powerpc/64s/exception: machine check pseries should always run the early handlerNicholas Piggin
Now that pseries with fwnmi registered runs the early machine check handler, there is no good reason to special case the non-fwnmi case and skip the early handler. Reducing the code and number of paths is a top priority for asm code, it's better to handle this in C where possible (and the pseries early handler is a no-op if fwnmi is not registered). Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-6-npiggin@gmail.com
2019-08-30powerpc/64s/exception: machine check adjust RFI targetNicholas Piggin
The host kernel delivery case for powernv does RFI_TO_USER_OR_KERNEL, but should just use RFI_TO_KERNEL which makes it clear this is not a user case. This is not a bug because RFI_TO_USER_OR_KERNEL deals with kernel returns just fine. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-5-npiggin@gmail.com
2019-08-30powerpc/64s/exception: machine check fix KVM guest testNicholas Piggin
The machine_check_handle_early hypervisor guest test is skipped if !HVMODE or MSR[HV]=0, which is wrong for PR or nested hypervisors that could be running a guest in this state. Test HSTATE_IN_GUEST up front and use that to branch out to the KVM handler, then MSR[PR] alone can test for this kernel's userspace. This matches all other interrupt handling. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-4-npiggin@gmail.com
2019-08-30powerpc/64s/exception: machine check remove bitrotted commentNicholas Piggin
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-3-npiggin@gmail.com
2019-08-30powerpc/64s/exception: machine check fwnmi remove HV caseNicholas Piggin
fwnmi does not trigger in HV mode, so remove always-true feature test. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190802105709.27696-2-npiggin@gmail.com
2019-08-30powerpc/pseries/svm: Export guest SVM status to user space via sysfsRyan Grimm
User space might want to know it's running in a secure VM. It can't do a mfmsr because mfmsr is a privileged instruction. The solution here is to create a cpu attribute: /sys/devices/system/cpu/svm which will read 0 or 1 based on the S bit of the current CPU. Signed-off-by: Ryan Grimm <grimm@linux.vnet.ibm.com> Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190820021326.6884-12-bauerman@linux.ibm.com
2019-08-30powerpc/pseries/svm: Unshare all pages before kexecing a new kernelRam Pai
A new kernel deserves a clean slate. Any pages shared with the hypervisor is unshared before invoking the new kernel. However there are exceptions. If the new kernel is invoked to dump the current kernel, or if there is a explicit request to preserve the state of the current kernel, unsharing of pages is skipped. NOTE: While testing crashkernel, make sure at least 256M is reserved for crashkernel. Otherwise SWIOTLB allocation will fail and crash kernel will fail to boot. Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190820021326.6884-11-bauerman@linux.ibm.com
2019-08-30powerpc/pseries/svm: Use shared memory for LPPACA structuresAnshuman Khandual
LPPACA structures need to be shared with the host. Hence they need to be in shared memory. Instead of allocating individual chunks of memory for a given structure from memblock, a contiguous chunk of memory is allocated and then converted into shared memory. Subsequent allocation requests will come from the contiguous chunk which will be always shared memory for all structures. While we are able to use a kmem_cache constructor for the Debug Trace Log, LPPACAs are allocated very early in the boot process (before SLUB is available) so we need to use a simpler scheme here. Introduce helper is_svm_platform() which uses the S bit of the MSR to tell whether we're running as a secure guest. Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com> Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190820021326.6884-9-bauerman@linux.ibm.com
2019-08-30powerpc/pseries: Add and use LPPACA_SIZE constantThiago Jung Bauermann
Helps document what the hard-coded number means. Also take the opportunity to fix an #endif comment. Suggested-by: Alexey Kardashevskiy <aik@linux.ibm.com> Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190820021326.6884-8-bauerman@linux.ibm.com
2019-08-30powerpc/prom_init: Add the ESM call to prom_initRam Pai
Make the Enter-Secure-Mode (ESM) ultravisor call to switch the VM to secure mode. Pass kernel base address and FDT address so that the Ultravisor is able to verify the integrity of the VM using information from the ESM blob. Add "svm=" command line option to turn on switching to secure mode. Signed-off-by: Ram Pai <linuxram@us.ibm.com> [ andmike: Generate an RTAS os-term hcall when the ESM ucall fails. ] Signed-off-by: Michael Anderson <andmike@linux.ibm.com> [ bauerman: Cleaned up the code a bit. ] Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190820021326.6884-5-bauerman@linux.ibm.com
2019-08-30powerpc/pseries: Introduce option to build secure virtual machinesThiago Jung Bauermann
Introduce CONFIG_PPC_SVM to control support for secure guests and include Ultravisor-related helpers when it is selected Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190820021326.6884-3-bauerman@linux.ibm.com
2019-08-30Merge branch 'topic/ppc-kvm' into nextMichael Ellerman
Merge our ppc-kvm topic branch to bring in the Ultravisor support patches.
2019-08-30powerpc/kvm: Use UV_RETURN ucall to return to ultravisorSukadev Bhattiprolu
When an SVM makes an hypercall or incurs some other exception, the Ultravisor usually forwards (a.k.a. reflects) the exceptions to the Hypervisor. After processing the exception, Hypervisor uses the UV_RETURN ultracall to return control back to the SVM. The expected register state on entry to this ultracall is: * Non-volatile registers are restored to their original values. * If returning from an hypercall, register R0 contains the return value (unlike other ultracalls) and, registers R4 through R12 contain any output values of the hypercall. * R3 contains the ultracall number, i.e UV_RETURN. * If returning with a synthesized interrupt, R2 contains the synthesized interrupt number. Thanks to input from Paul Mackerras, Ram Pai and Mike Anderson. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Claudio Carvalho <cclaudio@linux.ibm.com> Acked-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190822034838.27876-8-cclaudio@linux.ibm.com
2019-08-30powerpc/powernv: Introduce FW_FEATURE_ULTRAVISORClaudio Carvalho
In PEF enabled systems, some of the resources which were previously hypervisor privileged are now ultravisor privileged and controlled by the ultravisor firmware. This adds FW_FEATURE_ULTRAVISOR to indicate if PEF is enabled. The host kernel can use FW_FEATURE_ULTRAVISOR, for instance, to skip accessing resources (e.g. PTCR and LDBAR) in case PEF is enabled. Signed-off-by: Claudio Carvalho <cclaudio@linux.ibm.com> [ andmike: Device node name to "ibm,ultravisor" ] Signed-off-by: Michael Anderson <andmike@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190822034838.27876-4-cclaudio@linux.ibm.com
2019-08-30powerpc/kernel: Add ucall_norets() ultravisor call handlerClaudio Carvalho
The ultracalls (ucalls for short) allow the Secure Virtual Machines (SVM)s and hypervisor to request services from the ultravisor such as accessing a register or memory region that can only be accessed when running in ultravisor-privileged mode. This patch adds the ucall_norets() ultravisor call handler. The specific service needed from an ucall is specified in register R3 (the first parameter to the ucall). Other parameters to the ucall, if any, are specified in registers R4 through R12. Return value of all ucalls is in register R3. Other output values from the ucall, if any, are returned in registers R4 through R12. Each ucall returns specific error codes, applicable in the context of the ucall. However, like with the PowerPC Architecture Platform Reference (PAPR), if no specific error code is defined for a particular situation, then the ucall will fallback to an erroneous parameter-position based code. i.e U_PARAMETER, U_P2, U_P3 etc depending on the ucall parameter that may have caused the error. Every host kernel (powernv) needs to be able to do ucalls in case it ends up being run in a machine with ultravisor enabled. Otherwise, the kernel may crash early in boot trying to access ultravisor resources, for instance, trying to set the partition table entry 0. Secure guests also need to be able to do ucalls and its kernel may not have CONFIG_PPC_POWERNV=y. For that reason, the ucall.S file is placed under arch/powerpc/kernel. If ultravisor is not enabled, the ucalls will be redirected to the hypervisor which must handle/fail the call. Thanks to inputs from Ram Pai and Michael Anderson. Signed-off-by: Claudio Carvalho <cclaudio@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190822034838.27876-3-cclaudio@linux.ibm.com
2019-08-30powerpc: Add PowerPC Capabilities ELF noteClaudio Carvalho
Add the PowerPC name and the PPC_ELFNOTE_CAPABILITIES type in the kernel binary ELF note. This type is a bitmap that can be used to advertise kernel capabilities to userland. This patch also defines PPCCAP_ULTRAVISOR_BIT as being the bit zero. Suggested-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Claudio Carvalho <cclaudio@linux.ibm.com> [ maxiwell: Define the 'PowerPC' type in the elfnote.h ] Signed-off-by: Maxiwell S. Garcia <maxiwell@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190829155021.2915-2-maxiwell@linux.ibm.com
2019-08-30powerpc/powernv/ioda: Remove obsolete iommu_table_ops::exchange callbacksAlexey Kardashevskiy
As now we have xchg_no_kill/tce_kill, these are not used anymore so remove them. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190829085252.72370-6-aik@ozlabs.ru
2019-08-30powerpc/powernv/ioda: Split out TCE invalidation from TCE updatesAlexey Kardashevskiy
At the moment updates in a TCE table are made by iommu_table_ops::exchange which update one TCE and invalidates an entry in the PHB/NPU TCE cache via set of registers called "TCE Kill" (hence the naming). Writing a TCE is a simple xchg() but invalidating the TCE cache is a relatively expensive OPAL call. Mapping a 100GB guest with PCI+NPU passed through devices takes about 20s. Thankfully we can do better. Since such big mappings happen at the boot time and when memory is plugged/onlined (i.e. not often), these requests come in 512 pages so we call call OPAL 512 times less which brings 20s from the above to less than 10s. Also, since TCE caches can be flushed entirely, calling OPAL for 512 TCEs helps skiboot [1] to decide whether to flush the entire cache or not. This implements 2 new iommu_table_ops callbacks: - xchg_no_kill() to update a single TCE with no TCE invalidation; - tce_kill() to invalidate multiple TCEs. This uses the same xchg_no_kill() callback for IODA1/2. This implements 2 new wrappers on top of the new callbacks similar to the existing iommu_tce_xchg(). This does not use the new callbacks yet, the next patches will; so this should not cause any behavioral change. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190829085252.72370-2-aik@ozlabs.ru
2019-08-29powerpc/of/pci: Rewrite pci_parse_of_flagsAlexey Kardashevskiy
The existing code uses bunch of hardcoded values from the PCI Bus Binding to IEEE Std 1275 spec; and it does so in quite non-obvious way. This defines fields from the cell#0 of the "reg" property of a PCI device and uses them for parsing. This should cause no behavioral change. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> [mpe: Unsplit some 80/81 char lines, space the code with some newlines] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190829084417.71873-1-aik@ozlabs.ru
2019-08-28powerpc/64: remove support for kernel-mode syscallsNicholas Piggin
There is support for the kernel to execute the 'sc 0' instruction and make a system call to itself. This is a relic that is unused in the tree, therefore untested. It's also highly questionable for modules to be doing this. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190827033010.28090-3-npiggin@gmail.com
2019-08-28powerpc: convert to copy_thread_tlsNicholas Piggin
Commit 3033f14ab78c3 ("clone: support passing tls argument via C rather than pt_regs magic") introduced the HAVE_COPY_THREAD_TLS option. Use it to avoid a subtle assumption about the argument ordering of clone type syscalls. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190827033010.28090-2-npiggin@gmail.com