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* powerpc/mm: Increase the max addressable memory to 2PBAneesh Kumar K.V2018-10-143-36/+72
| | | | | | | | | | | | | | | | | | | | | | | Currently we limit the max addressable memory to 128TB. This patch increase the limit to 2PB. We can have devices like nvdimm which adds memory above 512TB limit. We still don't support regular system ram above 512TB. One of the challenge with that is the percpu allocator, that allocates per node memory and use the max distance between them as the percpu offsets. This means with large gap in address space ( system ram above 1PB) we will run out of vmalloc space to map the percpu allocation. In order to support addressable memory above 512TB, kernel should be able to linear map this range. To do that with hash translation we now add 4 context to kernel linear map region. Our per context addressable range is 512TB. We still keep VMALLOC and VMEMMAP region to old size. SLB miss handlers is updated to validate these limit. We also limit this update to SPARSEMEM_VMEMMAP and SPARSEMEM_EXTREME Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/mm/hash: Rename get_ea_context to get_user_contextAneesh Kumar K.V2018-10-142-3/+3
| | | | | | | | We will be adding get_kernel_context later. Update function name to indicate this handle context allocation user space address. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/64s/hash: Add some SLB debugging testsNicholas Piggin2018-10-141-0/+3
| | | | | | | | | | This adds CONFIG_DEBUG_VM checks to ensure: - The kernel stack is in the SLB after it's flushed and bolted. - We don't insert an SLB for an address that is aleady in the SLB. - The kernel SLB miss handler does not take an SLB miss. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/64s/hash: Simplify slb_flush_and_rebolt()Nicholas Piggin2018-10-141-1/+1
| | | | | | | | | | | | | slb_flush_and_rebolt() is misleading, it is called in virtual mode, so it can not possibly change the stack, so it should not be touching the shadow area. And since vmalloc is no longer bolted, it should not change any bolted mappings at all. Change the name to slb_flush_and_restore_bolted(), and have it just load the kernel stack from what's currently in the shadow SLB area. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/64s/hash: Add a SLB preload cacheNicholas Piggin2018-10-142-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When switching processes, currently all user SLBEs are cleared, and a few (exec_base, pc, and stack) are preloaded. In trivial testing with small apps, this tends to miss the heap and low 256MB segments, and it will also miss commonly accessed segments on large memory workloads. Add a simple round-robin preload cache that just inserts the last SLB miss into the head of the cache and preloads those at context switch time. Every 256 context switches, the oldest entry is removed from the cache to shrink the cache and require fewer slbmte if they are unused. Much more could go into this, including into the SLB entry reclaim side to track some LRU information etc, which would require a study of large memory workloads. But this is a simple thing we can do now that is an obvious win for common workloads. With the full series, process switching speed on the context_switch benchmark on POWER9/hash (with kernel speculation security masures disabled) increases from 140K/s to 178K/s (27%). POWER8 does not change much (within 1%), it's unclear why it does not see a big gain like POWER9. Booting to busybox init with 256MB segments has SLB misses go down from 945 to 69, and with 1T segments 900 to 21. These could almost all be eliminated by preloading a bit more carefully with ELF binary loading. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/64s/hash: Provide arch_setup_exec() hooks for hash slice setupNicholas Piggin2018-10-143-0/+9
| | | | | | | | This will be used by the SLB code in the next patch, but for now this sets the slb_addr_limit to the correct size for 32-bit tasks. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/64s/hash: Add SLB allocation status bitmapsNicholas Piggin2018-10-141-2/+4
| | | | | | | | | | Add 32-entry bitmaps to track the allocation status of the first 32 SLB entries, and whether they are user or kernel entries. These are used to allocate free SLB entries first, before resorting to the round robin allocator. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/64s/hash: Convert SLB miss handlers to CNicholas Piggin2018-10-142-8/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | This patch moves SLB miss handlers completely to C, using the standard exception handler macros to set up the stack and branch to C. This can be done because the segment containing the kernel stack is always bolted, so accessing it with relocation on will not cause an SLB exception. Arbitrary kernel memory must not be accessed when handling kernel space SLB misses, so care should be taken there. However user SLB misses can access any kernel memory, which can be used to move some fields out of the paca (in later patches). User SLB misses could quite easily reconcile IRQs and set up a first class kernel environment and exit via ret_from_except, however that doesn't seem to be necessary at the moment, so we only do that if a bad fault is encountered. [ Credit to Aneesh for bug fixes, error checks, and improvements to bad address handling, etc ] Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Disallow tracing for all of slb.c for now.] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/64: Interrupts save PPR on stack rather than thread_structNicholas Piggin2018-10-143-9/+10
| | | | | | | | | | | | | | | PPR is the odd register out when it comes to interrupt handling, it is saved in current->thread.ppr while all others are saved on the stack. The difficulty with this is that accessing thread.ppr can cause a SLB fault, but the SLB fault handler implementation in C change had assumed the normal exception entry handlers would not cause an SLB fault. Fix this by allocating room in the interrupt stack to save PPR. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc: Split user/kernel definitions of struct pt_regsMichael Ellerman2018-10-142-1/+33
| | | | | | | | | | | | | | | | | | | | | | We use a shared definition for struct pt_regs in uapi/asm/ptrace.h. That means the layout of the structure is ABI, ie. we can't change it. That would be fine if it was only used to describe the user-visible register state of a process, but it's also the struct we use in the kernel to describe the registers saved in an interrupt frame. We'd like more flexibility in the content (and possibly layout) of the kernel version of the struct, but currently that's not possible. So split the definition into a user-visible definition which remains unchanged, and a kernel internal one. At the moment they're still identical, and we check that at build time. That's because we have code (in ptrace etc.) that assumes that they are the same. We will fix that code in future patches, and then we can break the strict symmetry between the two structs. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/book3s64: Avoid multiple endian conversion in pte helpersChristophe Leroy2018-10-141-39/+32
| | | | | | | | | | | | In the same spirit as already done in pte query helpers, this patch changes pte setting helpers to perform endian conversions on the constants rather than on the pte value. In the meantime, it changes pte_access_permitted() to use pte helpers for the same reason. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/8xx: change name of a few page flags to avoid confusionChristophe Leroy2018-10-141-14/+14
| | | | | | | | | | | | | | | | | _PAGE_PRIVILEGED corresponds to the SH bit which doesn't protect against user access but only disables ASID verification on kernel accesses. User access is controlled with _PMD_USER flag. Name it _PAGE_SH instead of _PAGE_PRIVILEGED _PAGE_HUGE corresponds to the SPS bit which doesn't really tells that's it is a huge page but only that it is not a 4k page. Name it _PAGE_SPS instead of _PAGE_HUGE Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/mm: Get rid of pte-common.hChristophe Leroy2018-10-142-27/+24
| | | | | | | | | | Do not include pte-common.h in nohash/32/pgtable.h As that was the last includer, get rid of pte-common.h Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/mm: Define platform default caches related flagsChristophe Leroy2018-10-143-11/+7
| | | | | | | | | | | Cache related flags like _PAGE_COHERENT and _PAGE_WRITETHRU are defined on most platforms. The platforms not defining them don't define any alternative. So we can give them a NUL value directly for those platforms directly. Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/mm: Allow platforms to redefine some helpersChristophe Leroy2018-10-146-44/+91
| | | | | | | | | | | | | | | | | | | | | The 40xx defines _PAGE_HWWRITE while others don't. The 8xx defines _PAGE_RO instead of _PAGE_RW. The 8xx defines _PAGE_PRIVILEGED instead of _PAGE_USER. The 8xx defines _PAGE_HUGE and _PAGE_NA while others don't. Lets those platforms redefine pte_write(), pte_wrprotect() and pte_mkwrite() and get _PAGE_RO and _PAGE_HWWRITE off the common helpers. Lets the 8xx redefine pte_user(), pte_mkprivileged() and pte_mkuser() and get rid of _PAGE_PRIVILEGED and _PAGE_USER default values. Lets the 8xx redefine pte_mkhuge() and get rid of _PAGE_HUGE default value. Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/nohash/64: do not include pte-common.hChristophe Leroy2018-10-143-36/+44
| | | | | | | | | | | nohash/64 only uses book3e PTE flags, so it doesn't need pte-common.h This also allows to drop PAGE_SAO and H_PAGE_4K_PFN from pte_common.h as they are only used by PPC64 Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/mm: Distribute platform specific PAGE and PMD flags and definitionsChristophe Leroy2018-10-146-66/+159
| | | | | | | | | | | | | | | The base kernel PAGE_XXXX definition sets are more or less platform specific. Lets distribute them close to platform _PAGE_XXX flags definition, and customise them to their exact platform flags. Also defines _PAGE_PSIZE and _PTE_NONE_MASK for each platform allthough they are defined as 0. Do the same with _PMD flags like _PMD_USER and _PMD_PRESENT_MASK Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/mm: Move pte_user() into nohash/pgtable.hChristophe Leroy2018-10-142-13/+10
| | | | | | | | | | Now the pte-common.h is only for nohash platforms, lets move pte_user() helper out of pte-common.h to put it together with other helpers. Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/book3s/32: do not include pte-common.hChristophe Leroy2018-10-142-17/+101
| | | | | | | | | | | | | | As done for book3s/64, add necessary flags/defines in book3s/32/pgtable.h and do not include pte-common.h It allows in the meantime to remove all related hash definitions from pte-common.h and to also remove _PAGE_EXEC default as _PAGE_EXEC is defined on all platforms except book3s/32. Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/mm: move __P and __S tables in the common pgtable.hChristophe Leroy2018-10-143-40/+19
| | | | | | | | | __P and __S flags are the same for all platform and should remain as is in the future, so avoid duplication. Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/mm: drop unused page flagsChristophe Leroy2018-10-142-25/+2
| | | | | | | | | | | | | | | | | | | | | The following page flags in pte-common.h can be dropped: _PAGE_ENDIAN is only used in mm/fsl_booke_mmu.c and is defined in asm/nohash/32/pte-fsl-booke.h _PAGE_4K_PFN is nowhere defined nor used _PAGE_READ, _PAGE_WRITE and _PAGE_PTE are only defined and used in book3s/64 The following page flags in book3s/64/pgtable.h can be dropped as they are not used on this platform nor by common code. _PAGE_NA, _PAGE_RO, _PAGE_USER and _PAGE_PSIZE Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/mm: use pte helpers in generic codeChristophe Leroy2018-10-143-12/+12
| | | | | | | | | | | Get rid of platform specific _PAGE_XXXX in powerpc common code and use helpers instead. mm/dump_linuxpagetables.c will be handled separately Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/mm: add pte helpers to query and change pte flagsChristophe Leroy2018-10-145-0/+114
| | | | | | | | | | | | | | | | | | | | | In order to avoid using generic _PAGE_XXX flags in powerpc core functions, define helpers for all needed flags: - pte_mkuser() and pte_mkprivileged() to set/unset and/or unset/set _PAGE_USER and/or _PAGE_PRIVILEGED - pte_hashpte() to check if _PAGE_HASHPTE is set. - pte_ci() check if cache is inhibited (already existing on book3s/64) - pte_exprotect() to protect against execution - pte_exec() and pte_mkexec() to query and set page execution - pte_mkpte() to set _PAGE_PTE flag. - pte_hw_valid() to check _PAGE_PRESENT since pte_present does something different on book3s/64. On book3s/32 there is no exec protection, so pte_mkexec() and pte_exprotect() are nops and pte_exec() returns always true. Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/mm: move some nohash pte helpers in nohash/[32:64]/pgtable.hChristophe Leroy2018-10-143-28/+48
| | | | | | | | | | | | | In order to allow their use in nohash/32/pgtable.h, we have to move the following helpers in nohash/[32:64]/pgtable.h: - pte_mkwrite() - pte_mkdirty() - pte_mkyoung() - pte_wrprotect() Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/mm: don't use _PAGE_EXEC in book3s/32Christophe Leroy2018-10-141-1/+1
| | | | | | | | | | | book3s/32 doesn't define _PAGE_EXEC, so no need to use it. All other platforms define _PAGE_EXEC so no need to check it is not NUL when not book3s/32. Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc: handover page flags with a pgprot_t parameterChristophe Leroy2018-10-148-14/+11
| | | | | | | | | | In order to avoid multiple conversions, handover directly a pgprot_t to map_kernel_page() as already done for radix. Do the same for __ioremap_caller() and __ioremap_at(). Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/mm: properly set PAGE_KERNEL flags in ioremap()Christophe Leroy2018-10-141-0/+2
| | | | | | | | | | | Set PAGE_KERNEL directly in the caller and do not rely on a hack adding PAGE_KERNEL flags when _PAGE_PRESENT is not set. As already done for PPC64, use pgprot_cache() helpers instead of _PAGE_XXX flags in PPC32 ioremap() derived functions. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/32: Add ioremap_wt() and ioremap_coherent()Christophe Leroy2018-10-131-0/+9
| | | | | | | | | | | | Other arches have ioremap_wt() to map IO areas write-through. Implement it on PPC as well in order to avoid drivers using __ioremap(_PAGE_WRITETHRU) Also implement ioremap_coherent() to avoid drivers using __ioremap(_PAGE_COHERENT) Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc: Detect the presence of big-cores via "ibm, thread-groups"Gautham R. Shenoy2018-10-132-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | On IBM POWER9, the device tree exposes a property array identifed by "ibm,thread-groups" which will indicate which groups of threads share a particular set of resources. As of today we only have one form of grouping identifying the group of threads in the core that share the L1 cache, translation cache and instruction data flow. This patch adds helper functions to parse the contents of "ibm,thread-groups" and populate a per-cpu variable to cache information about siblings of each CPU that share the L1, traslation cache and instruction data-flow. It also defines a new global variable named "has_big_cores" which indicates if the cores on this configuration have multiple groups of threads that share L1 cache. For each online CPU, it maintains a cpu_smallcore_mask, which indicates the online siblings which share the L1-cache with it. Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/eeh: Cleanup eeh_ops.wait_state()Sam Bobroff2018-10-131-2/+2
| | | | | | | | | | | | | | | | | | | The wait_state member of eeh_ops does not need to be platform dependent; it's just logic around eeh_ops.get_state(). Therefore, merge the two (slightly different!) platform versions into a new function, eeh_wait_state() and remove the eeh_ops member. While doing this, also correct: * The wait logic, so that it never waits longer than max_wait. * The wait logic, so that it never waits less than EEH_STATE_MIN_WAIT_TIME. * One call site where the result is treated like a bit field before it's checked for negative error values. * In pseries_eeh_get_state(), rename the "state" parameter to "delay" because that's what it is. Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/eeh: Cleanup eeh_pe_state_mark()Sam Bobroff2018-10-131-0/+1
| | | | | | | | | | | | | Currently, eeh_pe_state_mark() marks a PE (and it's children) with a state and then performs additional processing if that state included EEH_PE_ISOLATED. The state parameter is always a constant at the call site, so rearrange eeh_pe_state_mark() into two functions and just call the appropriate one at each site. Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/eeh: Cleanup eeh_enabled()Sam Bobroff2018-10-131-5/+1
| | | | | Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/eeh: Cleanup list_head field namesSam Bobroff2018-10-131-6/+6
| | | | | | | | | | | | | | | | Instances of struct eeh_pe are placed in a tree structure using the fields "child_list" and "child", so place these next to each other in the definition. The field "child" is a list entry, so remove the unnecessary and misleading use of the list initializer, LIST_HEAD(), on it. The eeh_dev struct contains two list entry fields, called "list" and "rmv_list". Rename them to "entry" and "rmv_entry" and, as above, stop initializing them with LIST_HEAD(). Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/eeh: Cleanup unused field in eeh_devSam Bobroff2018-10-131-1/+0
| | | | | | | | The 'bus' member of struct eeh_dev is assigned to once but never used, so remove it. Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/eeh: Cleanup EEH_POSTPONED_PROBESam Bobroff2018-10-131-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | Currently a flag, EEH_POSTPONED_PROBE, is used to prevent an incorrect message "EEH: No capable adapters found" from being displayed during the boot of powernv systems. It is necessary because, on powernv, the call to eeh_probe_devices() made from eeh_init() is too early and EEH can't yet be enabled. A second call is made later from eeh_pnv_post_init(), which succeeds. (On pseries, the first call succeeds because PCI devices are set up early enough and no second call is made.) This can be simplified by moving the early call to eeh_probe_devices() from eeh_init() (where it's seen by both platforms) to pSeries_final_fixup(), so that each platform only calls eeh_probe_devices() once, at a point where it can succeed. This is slightly later in the boot sequence, but but still early enough and it is now in the same place in the sequence for both platforms (the pcibios_fixup hook). The display of the message can be cleaned up as well, by moving it into eeh_probe_devices(). Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* Merge branch 'fixes' into nextMichael Ellerman2018-10-091-0/+1
|\ | | | | | | | | | | Merge our fixes branch. It has a few important fixes that are needed for futher testing and also some commits that will conflict with content in next.
| * powerpc: Avoid code patching freed init sectionsMichael Neuling2018-09-181-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This stops us from doing code patching in init sections after they've been freed. In this chain: kvm_guest_init() -> kvm_use_magic_page() -> fault_in_pages_readable() -> __get_user() -> __get_user_nocheck() -> barrier_nospec(); We have a code patching location at barrier_nospec() and kvm_guest_init() is an init function. This whole chain gets inlined, so when we free the init section (hence kvm_guest_init()), this code goes away and hence should no longer be patched. We seen this as userspace memory corruption when using a memory checker while doing partition migration testing on powervm (this starts the code patching post migration via /sys/kernel/mobility/migration). In theory, it could also happen when using /sys/kernel/debug/powerpc/barrier_nospec. Cc: stable@vger.kernel.org # 4.13+ Signed-off-by: Michael Neuling <mikey@neuling.org> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | powerpc/tm: Remove msr_tm_active()Breno Leitao2018-10-031-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently msr_tm_active() is a wrapper around MSR_TM_ACTIVE() if CONFIG_PPC_TRANSACTIONAL_MEM is set, or it is just a function that returns false if CONFIG_PPC_TRANSACTIONAL_MEM is not set. This function is not necessary, since MSR_TM_ACTIVE() just do the same and could be used, removing the dualism and simplifying the code. This patchset remove every instance of msr_tm_active() and replaced it by MSR_TM_ACTIVE(). Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | powerpc/ptrace: Add support for PTRACE_SYSEMUBreno Leitao2018-10-032-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a patch that adds support for PTRACE_SYSEMU ptrace request in PowerPC architecture. When ptrace(PTRACE_SYSEMU, ...) request is called, it will be handled by the arch independent function ptrace_resume(), which will tag the task with the TIF_SYSCALL_EMU flag. This flag needs to be handled from a platform dependent point of view, which is what this patch does. This patch adds this task's flag as part of the _TIF_SYSCALL_DOTRACE, which is the MACRO that is used to trace syscalls at entrance/exit. Since TIF_SYSCALL_EMU is now part of _TIF_SYSCALL_DOTRACE, if the task has _TIF_SYSCALL_DOTRACE set, it will hit do_syscall_trace_enter() at syscall entrance and do_syscall_trace_leave() at syscall leave. do_syscall_trace_enter() needs to handle the TIF_SYSCALL_EMU flag properly, which will interrupt the syscall executing if TIF_SYSCALL_EMU is set. The output values should not be changed, i.e. the return value (r3) should contain the original syscall argument on exit. With this flag set, the syscall is not executed fundamentally, because do_syscall_trace_enter() is returning -1 which is bigger than NR_syscall, thus, skipping the syscall execution and exiting userspace. Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | powerpc: Redefine TIF_32BITS thread flagBreno Leitao2018-10-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Moving TIF_32BIT to use bit 20 instead of 4 in the task flag field. This change is making room for an upcoming new task macro (_TIF_SYSCALL_EMU) which is preferred to set a bit in the lower 16-bits part of the word. This upcoming flag macro will take part in a composed macro (_TIF_SYSCALL_DOTRACE) which will contain other flags as well, and it is preferred that the whole _TIF_SYSCALL_DOTRACE macro only sets the lower 16 bits of a word, so, it could be handled using immediate operations (as load immediate, add immediate, ...) where the immediate operand (SI) is limited to 16-bits. Another possible solution would be using the LOAD_REG_IMMEDIATE() macro to load a full 64-bits word immediate, but it takes 5 operations instead of one. Having TIF_32BITS being redefined to use an upper bit is not a problem since there is only one place in the assembly code where TIF_32BIT is being used, and it could be replaced with an operation with right shift (addis), since it is used alone, i.e. not being part of a composed macro, which has different bits set, and would require LOAD_REG_IMMEDIATE(). Tested on a 64 bits Big Endian machine running a 32 bits task. Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | powerpc/64: add stack protector supportChristophe Leroy2018-10-032-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | On PPC64, as register r13 points to the paca_struct at all time, this patch adds a copy of the canary there, which is copied at task_switch. That new canary is then used by using the following GCC options: -mstack-protector-guard=tls -mstack-protector-guard-reg=r13 -mstack-protector-guard-offset=offsetof(struct paca_struct, canary)) Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | powerpc/32: add stack protector supportChristophe Leroy2018-10-031-0/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This functionality was tentatively added in the past (commit 6533b7c16ee5 ("powerpc: Initial stack protector (-fstack-protector) support")) but had to be reverted (commit f2574030b0e3 ("powerpc: Revert the initial stack protector support") because of GCC implementing it differently whether it had been built with libc support or not. Now, GCC offers the possibility to manually set the stack-protector mode (global or tls) regardless of libc support. This time, the patch selects HAVE_STACKPROTECTOR only if -mstack-protector-guard=tls is supported by GCC. On PPC32, as register r2 points to current task_struct at all time, the stack_canary located inside task_struct can be used directly by using the following GCC options: -mstack-protector-guard=tls -mstack-protector-guard-reg=r2 -mstack-protector-guard-offset=offsetof(struct task_struct, stack_canary)) The protector is disabled for prom_init and bootx_init as it is too early to handle it properly. $ echo CORRUPT_STACK > /sys/kernel/debug/provoke-crash/DIRECT [ 134.943666] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: lkdtm_CORRUPT_STACK+0x64/0x64 [ 134.943666] [ 134.955414] CPU: 0 PID: 283 Comm: sh Not tainted 4.18.0-s3k-dev-12143-ga3272be41209 #835 [ 134.963380] Call Trace: [ 134.965860] [c6615d60] [c001f76c] panic+0x118/0x260 (unreliable) [ 134.971775] [c6615dc0] [c001f654] panic+0x0/0x260 [ 134.976435] [c6615dd0] [c032c368] lkdtm_CORRUPT_STACK_STRONG+0x0/0x64 [ 134.982769] [c6615e00] [ffffffff] 0xffffffff Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | powerpc/traps: merge unrecoverable_exception() and nonrecoverable_exception()Christophe Leroy2018-10-031-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | PPC32 uses nonrecoverable_exception() while PPC64 uses unrecoverable_exception(). Both functions are doing almost the same thing. This patch removes nonrecoverable_exception() Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | powerpc/mm:book3s: Enable THP migration supportAneesh Kumar K.V2018-10-031-0/+8
| | | | | | | | | | Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | powerpc/mm/thp: update pmd_trans_huge to check for pmd_presentAneesh Kumar K.V2018-10-032-0/+21
| | | | | | | | | | | | | | | | | | | | | | We need to make sure pmd_trans_huge returns false for a pmd migration entry. We mark the migration entry by clearing the _PAGE_PRESENT bit. We keep the _PAGE_PTE bit set to indicate a leaf page table entry. Hence we need to make sure we check for pmd_present() so that pmd_trans_huge won't return true on pmd migration entry. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | powerpc/mm/hugetlb/book3s: add _PAGE_PRESENT to hugepd pointer.Aneesh Kumar K.V2018-10-032-1/+4
| | | | | | | | | | | | | | | | | | This make hugetlb directory pointer similar to other page able entries. A hugepd entry is identified by lack of _PAGE_PTE bit set and directory size stored in HUGEPD_SHIFT_MASK. We update that to also look at _PAGE_PRESENT Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | powerpc/mm/book3s: Update pmd_present to look at _PAGE_PRESENT bitAneesh Kumar K.V2018-10-032-3/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With this patch we use 0x8000000000000000UL (_PAGE_PRESENT) to indicate a valid pgd/pud/pmd entry. We also switch the p**_present() to look at this bit. With pmd_present, we have a special case. We need to make sure we consider a pmd marked invalid during THP split as present. Right now we clear the _PAGE_PRESENT bit during a pmdp_invalidate. Inorder to consider this special case we add a new pte bit _PAGE_INVALID (mapped to _RPAGE_SW0). This bit is only used with _PAGE_PRESENT cleared. Hence we are not really losing a pte bit for this special case. pmd_present is also updated to look at _PAGE_INVALID. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | powerpc/powernv: Make possible for user to force a full ipl cec rebootVaibhav Jain2018-10-031-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Ever since fast reboot is enabled by default in opal, opal_cec_reboot() will use fast-reset instead of full IPL to perform system reboot. This leaves the user with no direct way to force a full IPL reboot except changing an nvram setting that persistently disables fast-reset for all subsequent reboots. This patch provides a more direct way for the user to force a one-shot full IPL reboot by passing the command line argument 'full' to the reboot command. So the user will be able to tweak the reboot behavior via: $ sudo reboot full # Force a full ipl reboot skipping fast-reset or $ sudo reboot # default reboot path (usually fast-reset) The reboot command passes the un-parsed command argument to the kernel via the 'Reboot' syscall which is then passed on to the arch function pnv_restart(). The patch updates pnv_restart() to handle this cmd-arg and issues opal_cec_reboot2 with OPAL_REBOOT_FULL_IPL to force a full IPL reset. Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | Revert "convert SLB miss handlers to C" and subsequent commitsMichael Ellerman2018-10-037-22/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commits: 5e46e29e6a97 ("powerpc/64s/hash: convert SLB miss handlers to C") 8fed04d0f6ae ("powerpc/64s/hash: remove user SLB data from the paca") 655deecf67b2 ("powerpc/64s/hash: SLB allocation status bitmaps") 2e1626744e8d ("powerpc/64s/hash: provide arch_setup_exec hooks for hash slice setup") 89ca4e126a3f ("powerpc/64s/hash: Add a SLB preload cache") This series had a few bugs, and the fixes are not all trivial. So revert most of it for now. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | powerpc: Fix duplicate const clang warning in user access codeAnton Blanchard2018-09-191-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This re-applies commit b91c1e3e7a6f ("powerpc: Fix duplicate const clang warning in user access code") (Jun 2015) which was undone in commits: f2ca80905929 ("powerpc/sparse: Constify the address pointer in __get_user_nosleep()") (Feb 2017) d466f6c5cac1 ("powerpc/sparse: Constify the address pointer in __get_user_nocheck()") (Feb 2017) f84ed59a612d ("powerpc/sparse: Constify the address pointer in __get_user_check()") (Feb 2017) We see a large number of duplicate const errors in the user access code when building with llvm/clang: include/linux/pagemap.h:576:8: warning: duplicate 'const' declaration specifier [-Wduplicate-decl-specifier] ret = __get_user(c, uaddr); The problem is we are doing const __typeof__(*(ptr)), which will hit the warning if ptr is marked const. Removing const does not seem to have any effect on GCC code generation. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Joel Stanley <joel@jms.id.au> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>