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* powerpc/64: Invalidate process table caching after setting process tablePaul Mackerras2017-03-031-0/+4
| | | | | | | | | | | | | The POWER9 MMU reads and caches entries from the process table. When we kexec from one kernel to another, the second kernel sets its process table pointer but doesn't currently do anything to make the CPU invalidate any cached entries from the old process table. This adds a tlbie (TLB invalidate entry) instruction with parameters to invalidate caching of the process table after the new process table is installed. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* Merge tag 'powerpc-4.11-2' of ↵Linus Torvalds2017-03-012-11/+17
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull more powerpc updates from Michael Ellerman: "Highlights include: - an update of the disassembly code used by xmon to the latest versions in binutils. We've received permission from all the authors of the relevant binutils changes to relicense their changes to the relevant files from GPLv3 to GPLv2, for inclusion in Linux. Thanks to Peter Bergner for doing the leg work to get permission from everyone. - addition of the "architected" Power9 CPU table entry, allowing us to boot in Power9 architected mode under a hypervisor. - updates to the Power9 PMU code. - implementation of clear_bit_unlock_is_negative_byte() to optimise unlock_page(). - Freescale updates from Scott: "Highlights include 8xx breakpoints and perf, t1042rdb display support, and board updates." Thanks to: Al Viro, Andrew Donnellan, Aneesh Kumar K.V, Balbir Singh, Douglas Miller, Frédéric Weisbecker, Gavin Shan, Madhavan Srinivasan, Michael Roth, Nathan Fontenot, Naveen N. Rao, Nicholas Piggin, Peter Bergner, Paul E. McKenney, Rashmica Gupta, Russell Currey, Sahil Mehta, Stewart Smith" * tag 'powerpc-4.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (48 commits) powerpc: Remove leftover cputime_to_nsecs call causing build error powerpc/mm/hash: Always clear UPRT and Host Radix bits when setting up CPU powerpc/optprobes: Fix TOC handling in optprobes trampoline powerpc/pseries: Advertise Hot Plug Event support to firmware cxl: fix nested locking hang during EEH hotplug powerpc/xmon: Dump memory in CPU endian format powerpc/pseries: Revert 'Auto-online hotplugged memory' powerpc/powernv: Make PCI non-optional powerpc/64: Implement clear_bit_unlock_is_negative_byte() powerpc/powernv: Remove unused variable in pnv_pci_sriov_disable() powerpc/kernel: Remove error message in pcibios_setup_phb_resources() powerpc/mm: Fix typo in set_pte_at() pci/hotplug/pnv-php: Disable MSI and PCI device properly pci/hotplug/pnv-php: Disable surprise hotplug capability on conflicts pci/hotplug/pnv-php: Remove WARN_ON() in pnv_php_put_slot() powerpc: Add POWER9 architected mode to cputable powerpc/perf: use is_kernel_addr macro in perf_get_misc_flags() powerpc/perf: Avoid FAB_*_MATCH checks for power9 powerpc/perf: Add restrictions to PMC5 in power9 DD1 powerpc/perf: Use Instruction Counter value ...
| * powerpc/mm: Fix typo in set_pte_at()Gavin Shan2017-02-171-3/+1Star
| | | | | | | | | | | | | | | | | | This fixes the typo about the _PAGE_PTE in set_pte_at() by changing "tryint" to "trying to". Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/mm: Blacklist SLB symbols from kprobeMichael Ellerman2017-02-171-0/+8
| | | | | | | | | | | | | | | | | | We can't sensibly take a trap at this point. So, blacklist these symbols. Reported-by: Anton Blanchard <anton@samba.org> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/mm: Convert slb_finish_load[_1T] to local symbolsMichael Ellerman2017-02-171-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | slb_finish_load and slb_finish_load_1T are both only used within slb_low.S, so make them local symbols. This makes the code a little clearer, as it's more obvious neither is intended to be an entry point from arbitrary other code, only the uses in this file. It also prevents them being used with kprobes and other tracing tools, which is good because we're not able to safely take traps at these locations, so making them local symbols avoids us needing to blacklist them. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | Merge tag 'powerpc-4.11-1' of ↵Linus Torvalds2017-02-2213-95/+391
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Highlights include: - Support for direct mapped LPC on POWER9, giving Linux direct access to devices that may be on there such as a UART. - Memory hotplug support for the Power9 Radix MMU. - Add new AUX vectors describing the processor's cache geometry, to be used by glibc. - The ability for a guest to ask the hypervisor to resize the guest's hash table, and in addition support for doing so automatically when memory is hotplugged into/out-of the guest. This allows the hash table to be sized based on the current memory usage of the guest, rather than the maximum possible memory usage. - Implementation of optprobes (kprobe optimisation) for powerpc. In addition there's the topic branch shared with the KVM tree, which includes support for guests to use the Radix MMU on Power9. Thanks to: Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju T, Anton Blanchard, Benjamin Herrenschmidt, Chris Packham, Daniel Axtens, Daniel Borkmann, David Gibson, Finn Thain, Gautham R. Shenoy, Gavin Shan, Greg Kurz, Joel Stanley, John Allen, Madhavan Srinivasan, Mahesh Salgaonkar, Markus Elfring, Michael Neuling, Nathan Fontenot, Naveen N. Rao, Nicholas Piggin, Paul Mackerras, Ravi Bangoria, Reza Arbab, Shailendra Singh, Vaibhav Jain, Wei Yongjun" * tag 'powerpc-4.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (129 commits) powerpc/mm/radix: Skip ptesync in pte update helpers powerpc/mm/radix: Use ptep_get_and_clear_full when clearing pte for full mm powerpc/mm/radix: Update pte update sequence for pte clear case powerpc/mm: Update PROTFAULT handling in the page fault path powerpc/xmon: Fix data-breakpoint powerpc/mm: Fix build break with BOOK3S_64=n and MEMORY_HOTPLUG=y powerpc/mm: Fix build break when CMA=n && SPAPR_TCE_IOMMU=y powerpc/mm: Fix build break with RADIX=y & HUGETLBFS=n powerpc/pseries: Fix typo in parameter description powerpc/kprobes: Remove kprobe_exceptions_notify() kprobes: Introduce weak variant of kprobe_exceptions_notify() powerpc/ftrace: Fix confusing help text for DISABLE_MPROFILE_KERNEL powerpc/powernv: Fix opal_exit tracepoint opcode powerpc: Add a prototype for mcount() so it can be versioned powerpc: Drop GPL from of_node_to_nid() export to match other arches powerpc/kprobes: Optimize kprobe in kretprobe_trampoline() powerpc/kprobes: Implement Optprobes powerpc/kprobes: Fixes for kprobe_lookup_name() on BE powerpc: Add helper to check if offset is within relative branch range powerpc/bpf: Introduce __PPC_SH64() ...
| * powerpc/mm: Update PROTFAULT handling in the page fault pathAneesh Kumar K.V2017-02-152-14/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With radix, we can get page fault with DSISR_PROTFAULT value set in case of PROT_NONE or autonuma mapping. The PROT_NONE case in handled by the vma check where we consider the access bad. For autonuma we should fall through and fixup the access mask correctly. Without this patch we trigger the WARN_ON() on radix. This code moves that WARN_ON() within a radix_enabled() check. I also moved the WARN_ON() outside the if condition making it apply for all type of faults (exec/write/read). It is also conditionalized for book3s, because BOOK3E can also get a PROTFAULT to handle the D/I cache sync. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * Merge branch 'topic/ppc-kvm' into nextMichael Ellerman2017-02-144-4/+52
| |\ | | | | | | | | | Merge the topic branch we're sharing with the kvm-ppc tree.
| | * powerpc/64: Make type of partition table flush depend on partition typePaul Mackerras2017-01-311-3/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When changing a partition table entry on POWER9, we do a particular form of the tlbie instruction which flushes all TLBs and caches of the partition table for a given logical partition ID (LPID). This instruction has a field in the instruction word, labelled R (radix), which should be 1 if the partition was previously a radix partition and 0 if it was a HPT partition. This implements that logic. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * powerpc/64: Export pgtable_cache and pgtable_cache_add for KVMPaul Mackerras2017-01-311-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | This exports the pgtable_cache array and the pgtable_cache_add function so that HV KVM can use them for allocating radix page tables for guests. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * powerpc/64: Enable use of radix MMU under hypervisor on POWER9Paul Mackerras2017-01-312-5/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To use radix as a guest, we first need to tell the hypervisor via the ibm,client-architecture call first that we support POWER9 and architecture v3.00, and that we can do either radix or hash and that we would like to choose later using an hcall (the H_REGISTER_PROC_TBL hcall). Then we need to check whether the hypervisor agreed to us using radix. We need to do this very early on in the kernel boot process before any of the MMU initialization is done. If the hypervisor doesn't agree, we can't use radix and therefore clear the radix MMU feature bit. Later, when we have set up our process table, which points to the radix tree for each process, we need to install that using the H_REGISTER_PROC_TBL hcall. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * powerpc/64: Don't try to use radix MMU under a hypervisorPaul Mackerras2017-01-311-0/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, if the kernel is running on a POWER9 processor under a hypervisor, it will try to use the radix MMU even though it doesn't have the necessary code to use radix under a hypervisor (it doesn't negotiate use of radix, and it doesn't do the H_REGISTER_PROC_TBL hcall). The result is that the guest kernel will crash when it tries to turn on the MMU. This fixes it by looking for the /chosen/ibm,architecture-vec-5 property, and if it exists, clears the radix MMU feature bit, before we decide whether to initialize for radix or HPT. This property is created by the hypervisor as a result of the guest calling the ibm,client-architecture-support method to indicate its capabilities, so it will indicate whether the hypervisor agreed to us using radix. Systems without a hypervisor may have this property also (for example, skiboot creates it), so we check the HV bit in the MSR to see whether we are running as a guest or not. If we are in hypervisor mode, then we can do whatever we like including using the radix MMU. The reason for using this property is that in future, when we have support for using radix under a hypervisor, we will need to check this property to see whether the hypervisor agreed to us using radix. Fixes: 2bfd65e45e87 ("powerpc/mm/radix: Add radix callbacks for early init routines") Cc: stable@vger.kernel.org # v4.7+ Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc/mm: Fix build break when CMA=n && SPAPR_TCE_IOMMU=yMichael Ellerman2017-02-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently the build breaks if CMA=n and SPAPR_TCE_IOMMU=y: arch/powerpc/mm/mmu_context_iommu.c: In function ‘mm_iommu_get’: arch/powerpc/mm/mmu_context_iommu.c:193:42: error: ‘MIGRATE_CMA’ undeclared (first use in this function) if (get_pageblock_migratetype(page) == MIGRATE_CMA) { ^~~~~~~~~~~ Fix it by using the existing is_migrate_cma_page(), which evaulates to false when CMA=n. Fixes: 2e5bbb5461f1 ("KVM: PPC: Book3S HV: Migrate pinned pages out of CMA") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc: Drop GPL from of_node_to_nid() export to match other archesShailendra Singh2017-02-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The generic implementation of of_node_to_nid() is EXPORT_SYMBOL, added in commit 298535c00a2c ("of, numa: Add NUMA of binding implementation."). The powerpc implementation added in commit 953039c8df7b ("[PATCH] powerpc: Allow devices to register with numa topology") is EXPORT_SYMBOL_GPL. This creates an inconsistency for of_node_to_nid() callers across architectures. Update the powerpc implementation to be exported consistently with the generic implementation. Signed-off-by: Shailendra Singh <shailendras@nvidia.com> Reviewed-by: Andy Ritger <aritger@nvidia.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc/pseries: Automatically resize HPT for memory hot add/removeDavid Gibson2017-02-102-0/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We've now implemented code in the pseries platform to use the new PAPR interface to allow resizing the hash page table (HPT) at runtime. This patch uses that interface to automatically attempt to resize the HPT when memory is hot added or removed. This tries to always keep the HPT at a reasonable size for our current memory size. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc/pseries: Add support for hash table resizingDavid Gibson2017-02-101-0/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds support for using two hypercalls to change the size of the main hash page table while running as a PAPR guest. For now these hypercalls are only in experimental qemu versions. The interface is two part: first H_RESIZE_HPT_PREPARE is used to allocate and prepare the new hash table. This may be slow, but can be done asynchronously. Then, H_RESIZE_HPT_COMMIT is used to switch to the new hash table. This requires that no CPUs be concurrently updating the HPT, and so must be run under stop_machine(). This also adds a debugfs file which can be used to manually control HPT resizing or testing purposes. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Paul Mackerras <paulus@samba.org> [mpe: Rename the debugfs file to "hpt_order"] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc/mm: unstub radix__vmemmap_remove_mapping()Reza Arbab2017-01-311-1/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use remove_pagetable() and friends for radix vmemmap removal. We do not require the special-case handling of vmemmap done in the x86 versions of these functions. This is because vmemmap_free() has already freed the mapped pages, and calls us with an aligned address range. So, add a few failsafe WARNs, but otherwise the code to remove physical mappings is already sufficient for vmemmap. Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc/mm: add radix__remove_section_mapping()Reza Arbab2017-01-312-1/+134
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Tear down and free the four-level page tables of physical mappings during memory hotremove. Borrow the basic structure of remove_pagetable() and friends from the identically-named x86 functions. Reduce the frequency of tlb flushes and page_table_lock spinlocks by only doing them in the outermost function. There was some question as to whether the locking is needed at all. Leave it for now, but we could consider dropping it. Memory must be offline to be removed, thus not in use. So there shouldn't be the sort of concurrent page walking activity here that might prompt us to use RCU. Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc/mm: add radix__create_section_mapping()Reza Arbab2017-01-312-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | Wire up memory hotplug page mapping for radix. Share the mapping function already used by radix_init_pgtable(). Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc/mm: refactor radix physical page mappingReza Arbab2017-01-311-38/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move the page mapping code in radix_init_pgtable() into a separate function that will also be used for memory hotplug. The current goto loop progressively decreases its mapping size as it covers the tail of a range whose end is unaligned. Change this to a for loop which can do the same for both ends of the range. Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc/powernv: Initialise nest mmuAlistair Popple2017-01-302-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | POWER9 contains an off core mmu called the nest mmu (NMMU). This is used by other hardware units on the chip to translate virtual addresses into real addresses. The unit attempting an address translation provides the majority of the context required for the translation request except for the base address of the partition table (ie. the PTCR) which needs to be programmed into the NMMU. This patch adds a call to OPAL to set the PTCR for the nest mmu in opal_init(). Signed-off-by: Alistair Popple <alistair@popple.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc/mm: Allow memory hotplug into an offline nodeReza Arbab2017-01-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Relax the check preventing us from hotplugging into an offline node. This limitation was added in commit 482ec7c403d2 ("[PATCH] powerpc numa: Support sparse online node map") to prevent adding resources to an uninitialized node. These days, there is no harm in doing so. The addition will actually cause the node to be initialized and onlined; add_memory_resource() calls hotadd_new_pgdat() (if necessary) and node_set_online(). Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc/mm: Simplify loop control in parse_numa_properties()Reza Arbab2017-01-301-8/+3Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The flow of the main loop in parse_numa_properties() is overly complicated. Simplify it to be less confusing and easier to read. No functional change. The end of the main loop in parse_numa_properties() looks like this: for_each_node_by_type(...) { ... if (!condition) { if (--ranges) goto new_range; else continue; } statement(); if (--ranges) goto new_range; /* else * continue; <- implicit, this is the end of the loop */ } The only effect of !condition is to skip execution of statement(). This can be rewritten in a simpler way: for_each_node_by_type(...) { ... if (condition) statement(); if (--ranges) goto new_range; } Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc/mm: Return directly after a failed __copy_from_user() in ↵Markus Elfring2017-01-251-3/+1Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | sys_subpage_prot() This function already has multiple exit points, so there's no harm adding another. Although it looks odd to return directly in a function which takes a lock, we've actually just dropped the mmap_sem in this code, so there's really no reason to go via a label. And it means we can drop the unhelpfully named out2 label. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> [mpe: Rewrite change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc/mm: Remove the debug hugepd_ok checkAneesh Kumar K.V2017-01-231-21/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | We don't do this for other page table entries. So lets keep this simple and always return false for hugepd check on a 64K page size config. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | | powerpc/64: Disable use of radix under a hypervisorPaul Mackerras2017-02-161-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, if the kernel is running on a POWER9 processor under a hypervisor, it may try to use the radix MMU even though it doesn't have the necessary code to do so (it doesn't negotiate use of radix, and it doesn't do the H_REGISTER_PROC_TBL hcall). If the hypervisor supports both radix and HPT, then it will set up the guest to use HPT (since the guest doesn't request radix in the CAS call), but if the radix feature bit is set in the ibm,pa-features property (which is valid, since ibm,pa-features is defined to represent the capabilities of the processor) the guest will try to use radix, resulting in a crash when it turns the MMU on. This makes the minimal fix for the current code, which is to disable radix unless we are running in hypervisor mode. Fixes: 2bfd65e45e87 ("powerpc/mm/radix: Add radix callbacks for early init routines") Cc: stable@vger.kernel.org # v4.7+ Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | | powerpc/mm/radix: Update ERAT flushes when invalidating TLBBenjamin Herrenschmidt2017-02-091-5/+1Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Three tiny changes to the ERAT flushing logic: First don't make it depend on DD1. It hasn't been decided yet but we might run DD2 in a mode that also requires explicit flushes for performance reasons so make it unconditional. We also add a missing isync, and finally remove the flush from _tlbiel_va as it is only necessary for congruence-class invalidations (PID, LPID and full TLB), not targetted invalidations. Fixes: 96ed1fe511a8 ("powerpc/mm/radix: Invalidate ERAT on tlbiel for POWER9 DD1") Cc: stable@vger.kernel.org # v4.9+ Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | | powerpc/mm: Fix spurrious segfaults on radix with autonumaBenjamin Herrenschmidt2017-02-081-16/+5Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When autonuma (Automatic NUMA balancing) marks a PTE inaccessible it clears all the protection bits but leave the PTE valid. With the Radix MMU, an attempt at executing from such a PTE will take a fault with bit 35 of SRR1 set "SRR1_ISI_N_OR_G". It is thus incorrect to treat all such faults as errors. We should pass them to handle_mm_fault() for autonuma to deal with. The case of pages that are really not executable is handled by the existing test for VM_EXEC further down. That leaves us with catching the kernel attempts at executing user pages. We can catch that earlier, even before we do find_vma. It is never valid on powerpc for the kernel to take an exec fault to begin with. So fold that test with the existing test for the kernel faulting on kernel addresses to bail out early. Fixes: 1d18ad026844 ("powerpc/mm: Detect instruction fetch denied and report") Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | | powerpc/mm: Use the correct pointer when setting a 2MB pteReza Arbab2017-01-301-2/+2
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | When setting a 2MB pte, radix__map_kernel_page() is using the address ptep = (pte_t *)pudp; Fix this conversion to use pmdp instead. Use pmdp_ptep() to do this instead of casting the pointer. Fixes: 2bfd65e45e87 ("powerpc/mm/radix: Add radix callbacks for early init routines") Cc: stable@vger.kernel.org # v4.7+ Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | powerpc/mm: Fix little-endian 4K hugetlbAneesh Kumar K.V2017-01-182-12/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we switched to big endian page table, we never updated the hugepd format such that it can work for both big endian and little endian config. This patch series update hugepd format such that it is looked at as __be64 value in big endian page table config. This patch also switch hugepd_t.pd from signed long to unsigned long. I did update the FSL hugepd_ok check to check for the top bit instead of checking > 0. Fixes: 5dc1ef858c12 ("powerpc/mm: Use big endian Linux page tables for book3s 64") Cc: stable@vger.kernel.org # v4.7+ Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | powerpc/mm/hugetlb: Don't panic when we don't find the default huge page sizeAneesh Kumar K.V2017-01-181-3/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The generic hugetlbfs code can handle not finding the default huge page size correctly. With HPAGE_SHIFT = 0 we see in dmesg: hugetlbfs: disabling because there are no supported hugepage sizes bash-4.2# echo 30 > /proc/sys/vm/nr_hugepages bash: echo: write error: Operation not supported Fixes: 03bb2d65900c ("powerpc: get hugetlbpage handling more generic") Reported-by: Chris Smart <chris@distroguy.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | powerpc: Fix pgtable pmd cache initNicholas Piggin2017-01-182-13/+6Star
| | | | | | | | | | | | | | | | | | | | | | | | | | Commit 9b081e10805cd ("powerpc: port 64 bits pgtable_cache to 32 bits") mixed up PMD_INDEX_SIZE and PMD_CACHE_INDEX a couple of times. This resulted in 64s/hash/4k configs to panic at boot with a false positive error check. Fix that and simplify error handling by moving the check to the caller. Fixes: 9b081e10805cd ("powerpc: port 64 bits pgtable_cache to 32 bits") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | powerpc/mm: Fix memory hotplug BUG() on radixReza Arbab2017-01-172-2/+20
|/ | | | | | | | | | | | | | | | | Memory hotplug is leading to hash page table calls, even on radix: arch_add_memory create_section_mapping htab_bolt_mapping BUG_ON(!ppc_md.hpte_insert); To fix, refactor {create,remove}_section_mapping() into hash__ and radix__ variants. Leave the radix versions stubbed for now. Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* Merge branch 'smp-urgent-for-linus' of ↵Linus Torvalds2016-12-251-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull SMP hotplug notifier removal from Thomas Gleixner: "This is the final cleanup of the hotplug notifier infrastructure. The series has been reintgrated in the last two days because there came a new driver using the old infrastructure via the SCSI tree. Summary: - convert the last leftover drivers utilizing notifiers - fixup for a completely broken hotplug user - prevent setup of already used states - removal of the notifiers - treewide cleanup of hotplug state names - consolidation of state space There is a sphinx based documentation pending, but that needs review from the documentation folks" * 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqchip/armada-xp: Consolidate hotplug state space irqchip/gic: Consolidate hotplug state space coresight/etm3/4x: Consolidate hotplug state space cpu/hotplug: Cleanup state names cpu/hotplug: Remove obsolete cpu hotplug register/unregister functions staging/lustre/libcfs: Convert to hotplug state machine scsi/bnx2i: Convert to hotplug state machine scsi/bnx2fc: Convert to hotplug state machine cpu/hotplug: Prevent overwriting of callbacks x86/msr: Remove bogus cleanup from the error path bus: arm-ccn: Prevent hotplug callback leak perf/x86/intel/cstate: Prevent hotplug callback leak ARM/imx/mmcd: Fix broken cpu hotplug handling scsi: qedi: Convert to hotplug state machine
| * cpu/hotplug: Cleanup state namesThomas Gleixner2016-12-251-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the state names got added a script was used to add the extra argument to the calls. The script basically converted the state constant to a string, but the cleanup to convert these strings into meaningful ones did not happen. Replace all the useless strings with 'subsys/xxx/yyy:state' strings which are used in all the other places already. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Link: http://lkml.kernel.org/r/20161221192112.085444152@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | Replace <asm/uaccess.h> with <linux/uaccess.h> globallyLinus Torvalds2016-12-245-5/+5
|/ | | | | | | | | | | | | This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'powerpc-4.10-1' of ↵Linus Torvalds2016-12-1617-290/+1325
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Highlights include: - Support for the kexec_file_load() syscall, which is a prereq for secure and trusted boot. - Prevent kernel execution of userspace on P9 Radix (similar to SMEP/PXN). - Sort the exception tables at build time, to save time at boot, and store them as relative offsets to save space in the kernel image & memory. - Allow building the kernel with thin archives, which should allow us to build an allyesconfig once some other fixes land. - Build fixes to allow us to correctly rebuild when changing the kernel endian from big to little or vice versa. - Plumbing so that we can avoid doing a full mm TLB flush on P9 Radix. - Initial stack protector support (-fstack-protector). - Support for dumping the radix (aka. Linux) and hash page tables via debugfs. - Fix an oops in cxl coredump generation when cxl_get_fd() is used. - Freescale updates from Scott: "Highlights include 8xx hugepage support, qbman fixes/cleanup, device tree updates, and some misc cleanup." - Many and varied fixes and minor enhancements as always. Thanks to: Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Anshuman Khandual, Anton Blanchard, Balbir Singh, Bartlomiej Zolnierkiewicz, Christophe Jaillet, Christophe Leroy, Denis Kirjanov, Elimar Riesebieter, Frederic Barrat, Gautham R. Shenoy, Geliang Tang, Geoff Levand, Jack Miller, Johan Hovold, Lars-Peter Clausen, Libin, Madhavan Srinivasan, Michael Neuling, Nathan Fontenot, Naveen N. Rao, Nicholas Piggin, Pan Xinhui, Peter Senna Tschudin, Rashmica Gupta, Rui Teng, Russell Currey, Scott Wood, Simon Guo, Suraj Jitindar Singh, Thiago Jung Bauermann, Tobias Klauser, Vaibhav Jain" [ And thanks to Michael, who took time off from a new baby to get this pull request done. - Linus ] * tag 'powerpc-4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (174 commits) powerpc/fsl/dts: add FMan node for t1042d4rdb powerpc/fsl/dts: add sg_2500_aqr105_phy4 alias on t1024rdb powerpc/fsl/dts: add QMan and BMan nodes on t1024 powerpc/fsl/dts: add QMan and BMan nodes on t1023 soc/fsl/qman: test: use DEFINE_SPINLOCK() powerpc/fsl-lbc: use DEFINE_SPINLOCK() powerpc/8xx: Implement support of hugepages powerpc: get hugetlbpage handling more generic powerpc: port 64 bits pgtable_cache to 32 bits powerpc/boot: Request no dynamic linker for boot wrapper soc/fsl/bman: Use resource_size instead of computation soc/fsl/qe: use builtin_platform_driver powerpc/fsl_pmc: use builtin_platform_driver powerpc/83xx/suspend: use builtin_platform_driver powerpc/ftrace: Fix the comments for ftrace_modify_code powerpc/perf: macros for power9 format encoding powerpc/perf: power9 raw event format encoding powerpc/perf: update attribute_group data structure powerpc/perf: factor out the event format field powerpc/mm/iommu, vfio/spapr: Put pages on VFIO container shutdown ...
| * Merge branch 'next' of ↵Michael Ellerman2016-12-166-236/+225Star
| |\ | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/scottwood/linux into next Freescale updates from Scott: "Highlights include 8xx hugepage support, qbman fixes/cleanup, device tree updates, and some misc cleanup."
| | * powerpc/8xx: Implement support of hugepagesChristophe Leroy2016-12-102-11/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 8xx uses a two level page table with two different linux page size support (4k and 16k). 8xx also support two different hugepage sizes 512k and 8M. In order to support them on linux we define two different page table layout. The size of pages is in the PGD entry, using PS field (bits 28-29): 00 : Small pages (4k or 16k) 01 : 512k pages 10 : reserved 11 : 8M pages For 512K hugepage size a pgd entry have the below format [<hugepte address >0101] . The hugepte table allocated will contain 8 entries pointing to 512K huge pte in 4k pages mode and 64 entries in 16k pages mode. For 8M in 16k mode, a pgd entry have the below format [<hugepte address >1101] . The hugepte table allocated will contain 8 entries pointing to 8M huge pte. For 8M in 4k mode, multiple pgd entries point to the same hugepte address and pgd entry will have the below format [<hugepte address>1101]. The hugepte table allocated will only have one entry. For the time being, we do not support CPU15 ERRATA when HUGETLB is selected Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> (v3, for the generic bits) Signed-off-by: Scott Wood <oss@buserror.net>
| | * powerpc: get hugetlbpage handling more genericChristophe Leroy2016-12-101-114/+81Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Today there are two implementations of hugetlbpages which are managed by exclusive #ifdefs: * FSL_BOOKE: several directory entries points to the same single hugepage * BOOK3S: one upper level directory entry points to a table of hugepages In preparation of implementation of hugepage support on the 8xx, we need a mix of the two above solutions, because the 8xx needs both cases depending on the size of pages: * In 4k page size mode, each PGD entry covers a 4M bytes area. It means that 2 PGD entries will be necessary to cover an 8M hugepage while a single PGD entry will cover 8x 512k hugepages. * In 16 page size mode, each PGD entry covers a 64M bytes area. It means that 8x 8M hugepages will be covered by one PGD entry and 64x 512k hugepages will be covers by one PGD entry. This patch: * removes #ifdefs in favor of if/else based on the range sizes * merges the two huge_pte_alloc() functions as they are pretty similar * merges the two hugetlbpage_init() functions as they are pretty similar Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> (v3) Signed-off-by: Scott Wood <oss@buserror.net>
| | * powerpc: port 64 bits pgtable_cache to 32 bitsChristophe Leroy2016-12-104-115/+109Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Today powerpc64 uses a set of pgtable_caches while powerpc32 uses standard pages when using 4k pages and a single pgtable_cache if using other size pages. In preparation of implementing huge pages on the 8xx, this patch replaces the specific powerpc32 handling by the 64 bits approach. This is done by: * moving 64 bits pgtable_cache_add() and pgtable_cache_init() in a new file called init-common.c * modifying pgtable_cache_init() to also handle the case without PMD * removing the 32 bits version of pgtable_cache_add() and pgtable_cache_init() * copying related header contents from 64 bits into both the book3s/32 and nohash/32 header files On the 8xx, the following cache sizes will be used: * 4k pages mode: - PGT_CACHE(10) for PGD - PGT_CACHE(3) for 512k hugepage tables * 16k pages mode: - PGT_CACHE(6) for PGD - PGT_CACHE(7) for 512k hugepage tables - PGT_CACHE(3) for 8M hugepage tables Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Scott Wood <oss@buserror.net>
| * | powerpc/mm/iommu, vfio/spapr: Put pages on VFIO container shutdownAlexey Kardashevskiy2016-12-022-14/+1Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | At the moment the userspace tool is expected to request pinning of the entire guest RAM when VFIO IOMMU SPAPR v2 driver is present. When the userspace process finishes, all the pinned pages need to be put; this is done as a part of the userspace memory context (MM) destruction which happens on the very last mmdrop(). This approach has a problem that a MM of the userspace process may live longer than the userspace process itself as kernel threads use userspace process MMs which was runnning on a CPU where the kernel thread was scheduled to. If this happened, the MM remains referenced until this exact kernel thread wakes up again and releases the very last reference to the MM, on an idle system this can take even hours. This moves preregistered regions tracking from MM to VFIO; insteads of using mm_iommu_table_group_mem_t::used, tce_container::prereg_list is added so each container releases regions which it has pre-registered. This changes the userspace interface to return EBUSY if a memory region is already registered in a container. However it should not have any practical effect as the only userspace tool available now does register memory region once per container anyway. As tce_iommu_register_pages/tce_iommu_unregister_pages are called under container->lock, this does not need additional locking. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Acked-by: Alex Williamson <alex.williamson@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc/iommu: Stop using @current in mm_iommu_xxxAlexey Kardashevskiy2016-12-021-29/+17Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This changes mm_iommu_xxx helpers to take mm_struct as a parameter instead of getting it from @current which in some situations may not have a valid reference to mm. This changes helpers to receive @mm and moves all references to @current to the caller, including checks for !current and !current->mm; checks in mm_iommu_preregistered() are removed as there is no caller yet. This moves the mm_iommu_adjust_locked_vm() call to the caller as it receives mm_iommu_table_group_mem_t but it needs mm. This should cause no behavioral change. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Acked-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc/iommu: Pass mm_struct to init/cleanup helpersAlexey Kardashevskiy2016-12-022-6/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We are going to get rid of @current references in mmu_context_boos3s64.c and cache mm_struct in the VFIO container. Since mm_context_t does not have reference counting, we will be using mm_struct which does have the reference counter. This changes mm_iommu_init/mm_iommu_cleanup to receive mm_struct rather than mm_context_t (which is embedded into mm). This should not cause any behavioral change. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc/mm: Fix page table dump build on non-Book3SMichael Ellerman2016-12-012-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the recent commit 1515ab932156 ("powerpc/mm: Dump hash table") we added code to dump the hage page table. Currently this can be selected to build on any platform. However it breaks the build if we're building for a non-Book3S platform, because none of the hash page table related defines and so on exist. So restrict it to building only on Book3S. Similarly in commit 8eb07b187000 ("powerpc/mm: Dump linux pagetables") we added code to dump the Linux page tables, which uses some constants which are only defined on Book3S - so guard those with an #ifdef. Fixes: 1515ab932156 ("powerpc/mm: Dump hash table") Fixes: 8eb07b187000 ("powerpc/mm: Dump linux pagetables") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc/mm: Fix no execute fault handling on pre-POWER5Balbir Singh2016-11-301-1/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Aneesh/Ben reported that the change to do_page_fault() we made in commit 1d18ad026844 ("powerpc/mm: Detect instruction fetch denied and report") needs to handle the case where CPU_FTR_COHERENT_ICACHE is missing but we have CPU_FTR_NOEXECUTE. In those cases the check added for SRR1_ISI_N_OR_G might trigger a false positive. This patch adds a check for CPU_FTR_COHERENT_ICACHE in addition to the MSR value. Fixes: 1d18ad026844 ("powerpc/mm: Detect instruction fetch denied and report") Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc/mm: update radix__ptep_set_access_flag to not do full mm tlb flushAneesh Kumar K.V2016-11-282-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we are updating a pte, we just need to flush the tlb mapping that pte. Right now we do a full mm flush because we don't track the page size. Now that we have page size details in pte use that to do the optimized flush Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc/mm: Add radix__tlb_flush_pte_p9_dd1()Aneesh Kumar K.V2016-11-281-0/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that we have page size details encoded in pte using software pte bits, use that to find the page size needed for tlb flush. This function should only be used on P9 DD1, so give it a horrible name to make that clear. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc/mm/radix: Prevent kernel execution of user spaceBalbir Singh2016-11-261-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ISA 3 defines new encoded access authority that allows instruction access prevention in privileged mode and allows normal access to problem state. This patch just enables IAMR (Instruction Authority Mask Register), enabling AMR would require more work. I've tested this with a buggy driver and a simple payload. The payload is specific to the build I've tested. mpe: Also tested with LKDTM: # echo EXEC_USERSPACE > /sys/kernel/debug/provoke-crash/DIRECT lkdtm: Performing direct entry EXEC_USERSPACE lkdtm: attempting ok execution at c0000000005bf560 lkdtm: attempting bad execution at 00003fff8d940000 Unable to handle kernel paging request for instruction fetch Faulting instruction address: 0x3fff8d940000 Oops: Kernel access of bad area, sig: 11 [#1] NIP: 00003fff8d940000 LR: c0000000005bfa58 CTR: 00003fff8d940000 REGS: c0000000f1fcf900 TRAP: 0400 Not tainted (4.9.0-rc5-compiler_gcc-6.2.0-00109-g956dbc06232a) MSR: 9000000010009033 <SF,HV,EE,ME,IR,DR,RI,LE> CR: 48002222 XER: 00000000 ... Call Trace: lkdtm_EXEC_USERSPACE+0x104/0x120 (unreliable) lkdtm_do_action+0x3c/0x80 direct_entry+0x100/0x1b0 full_proxy_write+0x94/0x100 __vfs_write+0x3c/0x1b0 vfs_write+0xcc/0x230 SyS_write+0x60/0x110 system_call+0x38/0xfc Signed-off-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | powerpc/mm: Detect instruction fetch denied and reportBalbir Singh2016-11-251-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | ISA 3 allows for prevention of instruction fetch and execution of user mode pages. If such an error occurs, SRR1 bit 35 reports the error. We catch and report the error in do_page_fault(). Signed-off-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>