user/sven/linux.git/arch, branch v5.4.70

mm: replace memmap_context by meminit_context

2020-10-07T06:01:29Z

commit c1d0da83358a2316d9be7f229f26126dbaa07468 upstream. Patch series "mm: fix memory to node bad links in sysfs", v3. Sometimes, firmware may expose interleaved memory layout like this: Early memory node ranges node 1: [mem 0x0000000000000000-0x000000011fffffff] node 2: [mem 0x0000000120000000-0x000000014fffffff] node 1: [mem 0x0000000150000000-0x00000001ffffffff] node 0: [mem 0x0000000200000000-0x000000048fffffff] node 2: [mem 0x0000000490000000-0x00000007ffffffff] In that case, we can see memory blocks assigned to multiple nodes in sysfs: $ ls -l /sys/devices/system/memory/memory21 total 0 lrwxrwxrwx 1 root root 0 Aug 24 05:27 node1 -> ../../node/node1 lrwxrwxrwx 1 root root 0 Aug 24 05:27 node2 -> ../../node/node2 -rw-r--r-- 1 root root 65536 Aug 24 05:27 online -r--r--r-- 1 root root 65536 Aug 24 05:27 phys_device -r--r--r-- 1 root root 65536 Aug 24 05:27 phys_index drwxr-xr-x 2 root root 0 Aug 24 05:27 power -r--r--r-- 1 root root 65536 Aug 24 05:27 removable -rw-r--r-- 1 root root 65536 Aug 24 05:27 state lrwxrwxrwx 1 root root 0 Aug 24 05:25 subsystem -> ../../../../bus/memory -rw-r--r-- 1 root root 65536 Aug 24 05:25 uevent -r--r--r-- 1 root root 65536 Aug 24 05:27 valid_zones The same applies in the node's directory with a memory21 link in both the node1 and node2's directory. This is wrong but doesn't prevent the system to run. However when later, one of these memory blocks is hot-unplugged and then hot-plugged, the system is detecting an inconsistency in the sysfs layout and a BUG_ON() is raised: kernel BUG at /Users/laurent/src/linux-ppc/mm/memory_hotplug.c:1084! LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries Modules linked in: rpadlpar_io rpaphp pseries_rng rng_core vmx_crypto gf128mul binfmt_misc ip_tables x_tables xfs libcrc32c crc32c_vpmsum autofs4 CPU: 8 PID: 10256 Comm: drmgr Not tainted 5.9.0-rc1+ #25 Call Trace: add_memory_resource+0x23c/0x340 (unreliable) __add_memory+0x5c/0xf0 dlpar_add_lmb+0x1b4/0x500 dlpar_memory+0x1f8/0xb80 handle_dlpar_errorlog+0xc0/0x190 dlpar_store+0x198/0x4a0 kobj_attr_store+0x30/0x50 sysfs_kf_write+0x64/0x90 kernfs_fop_write+0x1b0/0x290 vfs_write+0xe8/0x290 ksys_write+0xdc/0x130 system_call_exception+0x160/0x270 system_call_common+0xf0/0x27c This has been seen on PowerPC LPAR. The root cause of this issue is that when node's memory is registered, the range used can overlap another node's range, thus the memory block is registered to multiple nodes in sysfs. There are two issues here: (a) The sysfs memory and node's layouts are broken due to these multiple links (b) The link errors in link_mem_sections() should not lead to a system panic. To address (a) register_mem_sect_under_node should not rely on the system state to detect whether the link operation is triggered by a hot plug operation or not. This is addressed by the patches 1 and 2 of this series. Issue (b) will be addressed separately. This patch (of 2): The memmap_context enum is used to detect whether a memory operation is due to a hot-add operation or happening at boot time. Make it general to the hotplug operation and rename it as meminit_context. There is no functional change introduced by this patch Suggested-by: David Hildenbrand Signed-off-by: Laurent Dufour Signed-off-by: Andrew Morton Reviewed-by: David Hildenbrand Reviewed-by: Oscar Salvador Acked-by: Michal Hocko Cc: Greg Kroah-Hartman Cc: "Rafael J . Wysocki" Cc: Nathan Lynch Cc: Scott Cheloha Cc: Tony Luck Cc: Fenghua Yu Cc: Link: https://lkml.kernel.org/r/20200915094143.79181-1-ldufour@linux.ibm.com Link: https://lkml.kernel.org/r/20200915132624.9723-1-ldufour@linux.ibm.com Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

KVM: arm64: Assume write fault on S1PTW permission fault on instruction fetch

2020-10-01T11:18:25Z

commit c4ad98e4b72cb5be30ea282fce935248f2300e62 upstream. KVM currently assumes that an instruction abort can never be a write. This is in general true, except when the abort is triggered by a S1PTW on instruction fetch that tries to update the S1 page tables (to set AF, for example). This can happen if the page tables have been paged out and brought back in without seeing a direct write to them (they are thus marked read only), and the fault handling code will make the PT executable(!) instead of writable. The guest gets stuck forever. In these conditions, the permission fault must be considered as a write so that the Stage-1 update can take place. This is essentially the I-side equivalent of the problem fixed by 60e21a0ef54c ("arm64: KVM: Take S1 walks into account when determining S2 write faults"). Update kvm_is_write_fault() to return true on IABT+S1PTW, and introduce kvm_vcpu_trap_is_exec_fault() that only return true when no faulting on a S1 fault. Additionally, kvm_vcpu_dabt_iss1tw() is renamed to kvm_vcpu_abt_iss1tw(), as the above makes it plain that it isn't specific to data abort. Signed-off-by: Marc Zyngier Reviewed-by: Will Deacon Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200915104218.1284701-2-maz@kernel.org Signed-off-by: Greg Kroah-Hartman

mm/gup: fix gup_fast with dynamic page table folding

2020-10-01T11:18:24Z

commit d3f7b1bb204099f2f7306318896223e8599bb6a2 upstream. Currently to make sure that every page table entry is read just once gup_fast walks perform READ_ONCE and pass pXd value down to the next gup_pXd_range function by value e.g.: static int gup_pud_range(p4d_t p4d, unsigned long addr, unsigned long end, unsigned int flags, struct page **pages, int *nr) ... pudp = pud_offset(&p4d, addr); This function passes a reference on that local value copy to pXd_offset, and might get the very same pointer in return. This happens when the level is folded (on most arches), and that pointer should not be iterated. On s390 due to the fact that each task might have different 5,4 or 3-level address translation and hence different levels folded the logic is more complex and non-iteratable pointer to a local copy leads to severe problems. Here is an example of what happens with gup_fast on s390, for a task with 3-level paging, crossing a 2 GB pud boundary: // addr = 0x1007ffff000, end = 0x10080001000 static int gup_pud_range(p4d_t p4d, unsigned long addr, unsigned long end, unsigned int flags, struct page **pages, int *nr) { unsigned long next; pud_t *pudp; // pud_offset returns &p4d itself (a pointer to a value on stack) pudp = pud_offset(&p4d, addr); do { // on second iteratation reading "random" stack value pud_t pud = READ_ONCE(*pudp); // next = 0x10080000000, due to PUD_SIZE/MASK != PGDIR_SIZE/MASK on s390 next = pud_addr_end(addr, end); ... } while (pudp++, addr = next, addr != end); // pudp++ iterating over stack return 1; } This happens since s390 moved to common gup code with commit d1874a0c2805 ("s390/mm: make the pxd_offset functions more robust") and commit 1a42010cdc26 ("s390/mm: convert to the generic get_user_pages_fast code"). s390 tried to mimic static level folding by changing pXd_offset primitives to always calculate top level page table offset in pgd_offset and just return the value passed when pXd_offset has to act as folded. What is crucial for gup_fast and what has been overlooked is that PxD_SIZE/MASK and thus pXd_addr_end should also change correspondingly. And the latter is not possible with dynamic folding. To fix the issue in addition to pXd values pass original pXdp pointers down to gup_pXd_range functions. And introduce pXd_offset_lockless helpers, which take an additional pXd entry value parameter. This has already been discussed in https://lkml.kernel.org/r/20190418100218.0a4afd51@mschwideX1 Fixes: 1a42010cdc26 ("s390/mm: convert to the generic get_user_pages_fast code") Signed-off-by: Vasily Gorbik Signed-off-by: Andrew Morton Reviewed-by: Gerald Schaefer Reviewed-by: Alexander Gordeev Reviewed-by: Jason Gunthorpe Reviewed-by: Mike Rapoport Reviewed-by: John Hubbard Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Dave Hansen Cc: Russell King Cc: Catalin Marinas Cc: Will Deacon Cc: Michael Ellerman Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Jeff Dike Cc: Richard Weinberger Cc: Dave Hansen Cc: Andy Lutomirski Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Arnd Bergmann Cc: Andrey Ryabinin Cc: Heiko Carstens Cc: Christian Borntraeger Cc: Claudio Imbrenda Cc: [5.2+] Link: https://lkml.kernel.org/r/patch.git-943f1e5dcff2.your-ad-here.call-01599856292-ext-8676@work.hours Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

x86/ioapic: Unbreak check_timer()

2020-10-01T11:18:22Z

commit 86a82ae0b5095ea24c55898a3f025791e7958b21 upstream. Several people reported in the kernel bugzilla that between v4.12 and v4.13 the magic which works around broken hardware and BIOSes to find the proper timer interrupt delivery mode stopped working for some older affected platforms which need to fall back to ExtINT delivery mode. The reason is that the core code changed to keep track of the masked and disabled state of an interrupt line more accurately to avoid the expensive hardware operations. That broke an assumption in i8259_make_irq() which invokes disable_irq_nosync(); irq_set_chip_and_handler(); enable_irq(); Up to v4.12 this worked because enable_irq() unconditionally unmasked the interrupt line, but after the state tracking improvements this is not longer the case because the IO/APIC uses lazy disabling. So the line state is unmasked which means that enable_irq() does not call into the new irq chip to unmask it. In principle this is a shortcoming of the core code, but it's more than unclear whether the core code should try to reset state. At least this cannot be done unconditionally as that would break other existing use cases where the chip type is changed, e.g. when changing the trigger type, but the callers expect the state to be preserved. As the way how check_timer() is switching the delivery modes is truly unique, the obvious fix is to simply unmask the i8259 manually after changing the mode to ExtINT delivery and switching the irq chip to the legacy PIC. Note, that the fixes tag is not really precise, but identifies the commit which broke the assumptions in the IO/APIC and i8259 code and that's the kernel version to which this needs to be backported. Fixes: bf22ff45bed6 ("genirq: Avoid unnecessary low level irq function calls") Reported-by: p_c_chan@hotmail.com Reported-by: ecm4@mail.com Reported-by: perdigao1@yahoo.com Reported-by: matzes@users.sourceforge.net Reported-by: rvelascog@gmail.com Signed-off-by: Thomas Gleixner Tested-by: p_c_chan@hotmail.com Tested-by: matzes@users.sourceforge.net Cc: stable@vger.kernel.org Link: https://bugzilla.kernel.org/show_bug.cgi?id=197769 Signed-off-by: Greg Kroah-Hartman

arch/x86/lib/usercopy_64.c: fix __copy_user_flushcache() cache writeback

2020-10-01T11:18:21Z

commit a1cd6c2ae47ee10ff21e62475685d5b399e2ed4a upstream. If we copy less than 8 bytes and if the destination crosses a cache line, __copy_user_flushcache would invalidate only the first cache line. This patch makes it invalidate the second cache line as well. Fixes: 0aed55af88345b ("x86, uaccess: introduce copy_from_iter_flushcache for pmem / cache-bypass operations") Signed-off-by: Mikulas Patocka Signed-off-by: Andrew Morton Reviewed-by: Dan Williams Cc: Jan Kara Cc: Jeff Moyer Cc: Ingo Molnar Cc: Christoph Hellwig Cc: Toshi Kani Cc: "H. Peter Anvin" Cc: Al Viro Cc: Thomas Gleixner Cc: Matthew Wilcox Cc: Ross Zwisler Cc: Ingo Molnar Cc: Link: https://lkml.kernel.org/r/alpine.LRH.2.02.2009161451140.21915@file01.intranet.prod.int.rdu2.redhat.com Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

KVM: SVM: Add a dedicated INVD intercept routine

2020-10-01T11:18:21Z

[ Upstream commit 4bb05f30483fd21ea5413eaf1182768f251cf625 ] The INVD instruction intercept performs emulation. Emulation can't be done on an SEV guest because the guest memory is encrypted. Provide a dedicated intercept routine for the INVD intercept. And since the instruction is emulated as a NOP, just skip it instead. Fixes: 1654efcbc431 ("KVM: SVM: Add KVM_SEV_INIT command") Signed-off-by: Tom Lendacky Message-Id: Signed-off-by: Paolo Bonzini Signed-off-by: Sasha Levin

KVM: x86: Reset MMU context if guest toggles CR4.SMAP or CR4.PKE

2020-10-01T11:18:21Z

[ Upstream commit 8d214c481611b29458a57913bd786f0ac06f0605 ] Reset the MMU context during kvm_set_cr4() if SMAP or PKE is toggled. Recent commits to (correctly) not reload PDPTRs when SMAP/PKE are toggled inadvertantly skipped the MMU context reset due to the mask of bits that triggers PDPTR loads also being used to trigger MMU context resets. Fixes: 427890aff855 ("kvm: x86: Toggling CR4.SMAP does not load PDPTEs in PAE mode") Fixes: cb957adb4ea4 ("kvm: x86: Toggling CR4.PKE does not load PDPTEs in PAE mode") Cc: Jim Mattson Cc: Peter Shier Cc: Oliver Upton Signed-off-by: Sean Christopherson Message-Id: <20200923215352.17756-1-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini Signed-off-by: Sasha Levin

MIPS: Add the missing 'CPU_1074K' into __get_cpu_type()

2020-10-01T11:18:20Z

[ Upstream commit e393fbe6fa27af23f78df6e16a8fd2963578a8c4 ] Commit 442e14a2c55e ("MIPS: Add 1074K CPU support explicitly.") split 1074K from the 74K as an unique CPU type, while it missed to add the 'CPU_1074K' in __get_cpu_type(). So let's add it back. Fixes: 442e14a2c55e ("MIPS: Add 1074K CPU support explicitly.") Signed-off-by: Wei Li Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin

s390/init: add missing __init annotations

2020-10-01T11:18:14Z

[ Upstream commit fcb2b70cdb194157678fb1a75f9ff499aeba3d2a ] Add __init to reserve_memory_end, reserve_oldmem and remove_oldmem. Sometimes these functions are not inlined, and then the build complains about section mismatch. Signed-off-by: Ilya Leoshkevich Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik Signed-off-by: Sasha Levin

RISC-V: Take text_mutex in ftrace_init_nop()

2020-10-01T11:18:14Z

[ Upstream commit 66d18dbda8469a944dfec6c49d26d5946efba218 ] Without this we get lockdep failures. They're spurious failures as SMP isn't up when ftrace_init_nop() is called. As far as I can tell the easiest fix is to just take the lock, which also seems like the safest fix. Signed-off-by: Palmer Dabbelt Acked-by: Guo Ren Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin