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2019-11-30Merge tag 'powerpc-5.5-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Highlights: - Infrastructure for secure boot on some bare metal Power9 machines. The firmware support is still in development, so the code here won't actually activate secure boot on any existing systems. - A change to xmon (our crash handler / pseudo-debugger) to restrict it to read-only mode when the kernel is lockdown'ed, otherwise it's trivial to drop into xmon and modify kernel data, such as the lockdown state. - Support for KASLR on 32-bit BookE machines (Freescale / NXP). - Fixes for our flush_icache_range() and __kernel_sync_dicache() (VDSO) to work with memory ranges >4GB. - Some reworks of the pseries CMM (Cooperative Memory Management) driver to make it behave more like other balloon drivers and enable some cleanups of generic mm code. - A series of fixes to our hardware breakpoint support to properly handle unaligned watchpoint addresses. Plus a bunch of other smaller improvements, fixes and cleanups. Thanks to: Alastair D'Silva, Andrew Donnellan, Aneesh Kumar K.V, Anthony Steinhauser, Cédric Le Goater, Chris Packham, Chris Smart, Christophe Leroy, Christopher M. Riedl, Christoph Hellwig, Claudio Carvalho, Daniel Axtens, David Hildenbrand, Deb McLemore, Diana Craciun, Eric Richter, Geert Uytterhoeven, Greg Kroah-Hartman, Greg Kurz, Gustavo L. F. Walbon, Hari Bathini, Harish, Jason Yan, Krzysztof Kozlowski, Leonardo Bras, Mathieu Malaterre, Mauro S. M. Rodrigues, Michal Suchanek, Mimi Zohar, Nathan Chancellor, Nathan Lynch, Nayna Jain, Nick Desaulniers, Oliver O'Halloran, Qian Cai, Rasmus Villemoes, Ravi Bangoria, Sam Bobroff, Santosh Sivaraj, Scott Wood, Thomas Huth, Tyrel Datwyler, Vaibhav Jain, Valentin Longchamp, YueHaibing" * tag 'powerpc-5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (144 commits) powerpc/fixmap: fix crash with HIGHMEM x86/efi: remove unused variables powerpc: Define arch_is_kernel_initmem_freed() for lockdep powerpc/prom_init: Use -ffreestanding to avoid a reference to bcmp powerpc: Avoid clang warnings around setjmp and longjmp powerpc: Don't add -mabi= flags when building with Clang powerpc: Fix Kconfig indentation powerpc/fixmap: don't clear fixmap area in paging_init() selftests/powerpc: spectre_v2 test must be built 64-bit powerpc/powernv: Disable native PCIe port management powerpc/kexec: Move kexec files into a dedicated subdir. powerpc/32: Split kexec low level code out of misc_32.S powerpc/sysdev: drop simple gpio powerpc/83xx: map IMMR with a BAT. powerpc/32s: automatically allocate BAT in setbat() powerpc/ioremap: warn on early use of ioremap() powerpc: Add support for GENERIC_EARLY_IOREMAP powerpc/fixmap: Use __fix_to_virt() instead of fix_to_virt() powerpc/8xx: use the fixmapped IMMR in cpm_reset() powerpc/8xx: add __init to cpm1 init functions ...
2019-11-14KVM: PPC: Book3S HV: Flush link stack on guest exit to host kernelMichael Ellerman
On some systems that are vulnerable to Spectre v2, it is up to software to flush the link stack (return address stack), in order to protect against Spectre-RSB. When exiting from a guest we do some house keeping and then potentially exit to C code which is several stack frames deep in the host kernel. We will then execute a series of returns without preceeding calls, opening up the possiblity that the guest could have poisoned the link stack, and direct speculative execution of the host to a gadget of some sort. To prevent this we add a flush of the link stack on exit from a guest. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-11-14powerpc/book3s64: Fix link stack flush on context switchMichael Ellerman
In commit ee13cb249fab ("powerpc/64s: Add support for software count cache flush"), I added support for software to flush the count cache (indirect branch cache) on context switch if firmware told us that was the required mitigation for Spectre v2. As part of that code we also added a software flush of the link stack (return address stack), which protects against Spectre-RSB between user processes. That is all correct for CPUs that activate that mitigation, which is currently Power9 Nimbus DD2.3. What I got wrong is that on older CPUs, where firmware has disabled the count cache, we also need to flush the link stack on context switch. To fix it we create a new feature bit which is not set by firmware, which tells us we need to flush the link stack. We set that when firmware tells us that either of the existing Spectre v2 mitigations are enabled. Then we adjust the patching code so that if we see that feature bit we enable the link stack flush. If we're also told to flush the count cache in software then we fall through and do that also. On the older CPUs we don't need to do do the software count cache flush, firmware has disabled it, so in that case we patch in an early return after the link stack flush. The naming of some of the functions is awkward after this patch, because they're called "count cache" but they also do link stack. But we'll fix that up in a later commit to ease backporting. This is the fix for CVE-2019-18660. Reported-by: Anthony Steinhauser <asteinhauser@google.com> Fixes: ee13cb249fab ("powerpc/64s: Add support for software count cache flush") Cc: stable@vger.kernel.org # v4.4+ Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-11-13powerpc/64s: Fix debugfs_simple_attr.cocci warningsYueHaibing
Use DEFINE_DEBUGFS_ATTRIBUTE rather than DEFINE_SIMPLE_ATTRIBUTE for debugfs files. Semantic patch information: Rationale: DEFINE_SIMPLE_ATTRIBUTE + debugfs_create_file() imposes some significant overhead as compared to DEFINE_DEBUGFS_ATTRIBUTE + debugfs_create_file_unsafe(). Generated by: scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1543498518-107601-1-git-send-email-yuehaibing@huawei.com
2019-11-13powerpc/security: Fix wrong message when RFI Flush is disableGustavo L. F. Walbon
The issue was showing "Mitigation" message via sysfs whatever the state of "RFI Flush", but it should show "Vulnerable" when it is disabled. If you have "L1D private" feature enabled and not "RFI Flush" you are vulnerable to meltdown attacks. "RFI Flush" is the key feature to mitigate the meltdown whatever the "L1D private" state. SEC_FTR_L1D_THREAD_PRIV is a feature for Power9 only. So the message should be as the truth table shows: CPU | L1D private | RFI Flush | sysfs ----|-------------|-----------|------------------------------------- P9 | False | False | Vulnerable P9 | False | True | Mitigation: RFI Flush P9 | True | False | Vulnerable: L1D private per thread P9 | True | True | Mitigation: RFI Flush, L1D private per thread P8 | False | False | Vulnerable P8 | False | True | Mitigation: RFI Flush Output before this fix: # cat /sys/devices/system/cpu/vulnerabilities/meltdown Mitigation: RFI Flush, L1D private per thread # echo 0 > /sys/kernel/debug/powerpc/rfi_flush # cat /sys/devices/system/cpu/vulnerabilities/meltdown Mitigation: L1D private per thread Output after fix: # cat /sys/devices/system/cpu/vulnerabilities/meltdown Mitigation: RFI Flush, L1D private per thread # echo 0 > /sys/kernel/debug/powerpc/rfi_flush # cat /sys/devices/system/cpu/vulnerabilities/meltdown Vulnerable: L1D private per thread Signed-off-by: Gustavo L. F. Walbon <gwalbon@linux.ibm.com> Signed-off-by: Mauro S. M. Rodrigues <maurosr@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190502210907.42375-1-gwalbon@linux.ibm.com
2019-11-05powerpc/security: Fix debugfs data leak on 32-bitGeert Uytterhoeven
"powerpc_security_features" is "unsigned long", i.e. 32-bit or 64-bit, depending on the platform (PPC_FSL_BOOK3E or PPC_BOOK3S_64). Hence casting its address to "u64 *", and calling debugfs_create_x64() is wrong, and leaks 32-bit of nearby data to userspace on 32-bit platforms. While all currently defined SEC_FTR_* security feature flags fit in 32-bit, they all have "ULL" suffixes to make them 64-bit constants. Hence fix the leak by changing the type of "powerpc_security_features" (and the parameter types of its accessors) to "u64". This also allows to drop the cast. Fixes: 398af571128fe75f ("powerpc/security: Show powerpc_security_features in debugfs") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20191021142309.28105-1-geert+renesas@glider.be
2019-11-05powerpc/security/book3s64: Report L1TF status in sysfsAnthony Steinhauser
Some PowerPC CPUs are vulnerable to L1TF to the same extent as to Meltdown. It is also mitigated by flushing the L1D on privilege transition. Currently the sysfs gives a false negative on L1TF on CPUs that I verified to be vulnerable, a Power9 Talos II Boston 004e 1202, PowerNV T2P9D01. Signed-off-by: Anthony Steinhauser <asteinhauser@google.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> [mpe: Just have cpu_show_l1tf() call cpu_show_meltdown() directly] Link: https://lore.kernel.org/r/20191029190759.84821-1-asteinhauser@google.com
2019-08-27powerpc/64s: support nospectre_v2 cmdline optionChristopher M. Riedl
Add support for disabling the kernel implemented spectre v2 mitigation (count cache flush on context switch) via the nospectre_v2 and mitigations=off cmdline options. Suggested-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Christopher M. Riedl <cmr@informatik.wtf> Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190524024647.381-1-cmr@informatik.wtf
2019-05-10Merge tag 'powerpc-5.2-1' of ↵Linus Torvalds
ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Slightly delayed due to the issue with printk() calling probe_kernel_read() interacting with our new user access prevention stuff, but all fixed now. The only out-of-area changes are the addition of a cpuhp_state, small additions to Documentation and MAINTAINERS updates. Highlights: - Support for Kernel Userspace Access/Execution Prevention (like SMAP/SMEP/PAN/PXN) on some 64-bit and 32-bit CPUs. This prevents the kernel from accidentally accessing userspace outside copy_to/from_user(), or ever executing userspace. - KASAN support on 32-bit. - Rework of where we map the kernel, vmalloc, etc. on 64-bit hash to use the same address ranges we use with the Radix MMU. - A rewrite into C of large parts of our idle handling code for 64-bit Book3S (ie. power8 & power9). - A fast path entry for syscalls on 32-bit CPUs, for a 12-17% speedup in the null_syscall benchmark. - On 64-bit bare metal we have support for recovering from errors with the time base (our clocksource), however if that fails currently we hang in __delay() and never crash. We now have support for detecting that case and short circuiting __delay() so we at least panic() and reboot. - Add support for optionally enabling the DAWR on Power9, which had to be disabled by default due to a hardware erratum. This has the effect of enabling hardware breakpoints for GDB, the downside is a badly behaved program could crash the machine by pointing the DAWR at cache inhibited memory. This is opt-in obviously. - xmon, our crash handler, gets support for a read only mode where operations that could change memory or otherwise disturb the system are disabled. Plus many clean-ups, reworks and minor fixes etc. Thanks to: Christophe Leroy, Akshay Adiga, Alastair D'Silva, Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anton Blanchard, Ben Hutchings, Bo YU, Breno Leitao, Cédric Le Goater, Christopher M. Riedl, Christoph Hellwig, Colin Ian King, David Gibson, Ganesh Goudar, Gautham R. Shenoy, George Spelvin, Greg Kroah-Hartman, Greg Kurz, Horia Geantă, Jagadeesh Pagadala, Joel Stanley, Joe Perches, Julia Lawall, Laurentiu Tudor, Laurent Vivier, Lukas Bulwahn, Madhavan Srinivasan, Mahesh Salgaonkar, Mathieu Malaterre, Michael Neuling, Mukesh Ojha, Nathan Fontenot, Nathan Lynch, Nicholas Piggin, Nick Desaulniers, Oliver O'Halloran, Peng Hao, Qian Cai, Ravi Bangoria, Rick Lindsley, Russell Currey, Sachin Sant, Stewart Smith, Sukadev Bhattiprolu, Thomas Huth, Tobin C. Harding, Tyrel Datwyler, Valentin Schneider, Wei Yongjun, Wen Yang, YueHaibing" * tag 'powerpc-5.2-1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (205 commits) powerpc/64s: Use early_mmu_has_feature() in set_kuap() powerpc/book3s/64: check for NULL pointer in pgd_alloc() powerpc/mm: Fix hugetlb page initialization ocxl: Fix return value check in afu_ioctl() powerpc/mm: fix section mismatch for setup_kup() powerpc/mm: fix redundant inclusion of pgtable-frag.o in Makefile powerpc/mm: Fix makefile for KASAN powerpc/kasan: add missing/lost Makefile selftests/powerpc: Add a signal fuzzer selftest powerpc/booke64: set RI in default MSR ocxl: Provide global MMIO accessors for external drivers ocxl: move event_fd handling to frontend ocxl: afu_irq only deals with IRQ IDs, not offsets ocxl: Allow external drivers to use OpenCAPI contexts ocxl: Create a clear delineation between ocxl backend & frontend ocxl: Don't pass pci_dev around ocxl: Split pci.c ocxl: Remove some unused exported symbols ocxl: Remove superfluous 'extern' from headers ocxl: read_pasid never returns an error, so make it void ...
2019-05-06Merge branch 'core-speculation-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull speculation mitigation update from Ingo Molnar: "This adds the "mitigations=" bootline option, which offers a cross-arch set of options that will work on x86, PowerPC and s390 that will map to the arch specific option internally" * 'core-speculation-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: s390/speculation: Support 'mitigations=' cmdline option powerpc/speculation: Support 'mitigations=' cmdline option x86/speculation: Support 'mitigations=' cmdline option cpu/speculation: Add 'mitigations=' cmdline option
2019-05-03powerpc/security: Show powerpc_security_features in debugfsMichael Ellerman
This can be helpful for debugging problems with the security feature flags, especially on guests where the flags come from the hypervisor via an hcall and so can't be observed in the device tree. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-17powerpc/speculation: Support 'mitigations=' cmdline optionJosh Poimboeuf
Configure powerpc CPU runtime speculation bug mitigations in accordance with the 'mitigations=' cmdline option. This affects Meltdown, Spectre v1, Spectre v2, and Speculative Store Bypass. The default behavior is unchanged. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Jiri Kosina <jkosina@suse.cz> (on x86) Reviewed-by: Jiri Kosina <jkosina@suse.cz> Cc: Borislav Petkov <bp@alien8.de> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Jiri Kosina <jikos@kernel.org> Cc: Waiman Long <longman@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Jon Masters <jcm@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: linuxppc-dev@lists.ozlabs.org Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux-s390@vger.kernel.org Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-arch@vger.kernel.org Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Tyler Hicks <tyhicks@canonical.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Steven Price <steven.price@arm.com> Cc: Phil Auld <pauld@redhat.com> Link: https://lkml.kernel.org/r/245a606e1a42a558a310220312d9b6adb9159df6.1555085500.git.jpoimboe@redhat.com
2019-03-21powerpc/security: Fix spectre_v2 reportingMichael Ellerman
When I updated the spectre_v2 reporting to handle software count cache flush I got the logic wrong when there's no software count cache enabled at all. The result is that on systems with the software count cache flush disabled we print: Mitigation: Indirect branch cache disabled, Software count cache flush Which correctly indicates that the count cache is disabled, but incorrectly says the software count cache flush is enabled. The root of the problem is that we are trying to handle all combinations of options. But we know now that we only expect to see the software count cache flush enabled if the other options are false. So split the two cases, which simplifies the logic and fixes the bug. We were also missing a space before "(hardware accelerated)". The result is we see one of: Mitigation: Indirect branch serialisation (kernel only) Mitigation: Indirect branch cache disabled Mitigation: Software count cache flush Mitigation: Software count cache flush (hardware accelerated) Fixes: ee13cb249fab ("powerpc/64s: Add support for software count cache flush") Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Michael Neuling <mikey@neuling.org> Reviewed-by: Diana Craciun <diana.craciun@nxp.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20powerpc/fsl: Update Spectre v2 reportingDiana Craciun
Report branch predictor state flush as a mitigation for Spectre variant 2. Signed-off-by: Diana Craciun <diana.craciun@nxp.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20powerpc/fsl: Add nospectre_v2 command line argumentDiana Craciun
When the command line argument is present, the Spectre variant 2 mitigations are disabled. Signed-off-by: Diana Craciun <diana.craciun@nxp.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-20powerpc/fsl: Fix spectre_v2 mitigations reportingDiana Craciun
Currently for CONFIG_PPC_FSL_BOOK3E the spectre_v2 file is incorrect: $ cat /sys/devices/system/cpu/vulnerabilities/spectre_v2 "Mitigation: Software count cache flush" Which is wrong. Fix it to report vulnerable for now. Fixes: ee13cb249fab ("powerpc/64s: Add support for software count cache flush") Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Diana Craciun <diana.craciun@nxp.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-11-25powerpc/64s: Include cpu headerBreno Leitao
Current powerpc security.c file is defining functions, as cpu_show_meltdown(), cpu_show_spectre_v{1,2} and others, that are being declared at linux/cpu.h header without including the header file that contains these declarations. This is being reported by sparse, which thinks that these functions are static, due to the lack of declaration: arch/powerpc/kernel/security.c:105:9: warning: symbol 'cpu_show_meltdown' was not declared. Should it be static? arch/powerpc/kernel/security.c:139:9: warning: symbol 'cpu_show_spectre_v1' was not declared. Should it be static? arch/powerpc/kernel/security.c:161:9: warning: symbol 'cpu_show_spectre_v2' was not declared. Should it be static? arch/powerpc/kernel/security.c:209:6: warning: symbol 'stf_barrier' was not declared. Should it be static? arch/powerpc/kernel/security.c:289:9: warning: symbol 'cpu_show_spec_store_bypass' was not declared. Should it be static? This patch simply includes the proper header (linux/cpu.h) to match function definition and declaration. Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-08-08powerpc/64s: Add support for software count cache flushMichael Ellerman
Some CPU revisions support a mode where the count cache needs to be flushed by software on context switch. Additionally some revisions may have a hardware accelerated flush, in which case the software flush sequence can be shortened. If we detect the appropriate flag from firmware we patch a branch into _switch() which takes us to a count cache flush sequence. That sequence in turn may be patched to return early if we detect that the CPU supports accelerating the flush sequence in hardware. Add debugfs support for reporting the state of the flush, as well as runtime disabling it. And modify the spectre_v2 sysfs file to report the state of the software flush. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-08-08powerpc/64: Make meltdown reporting Book3S 64 specificDiana Craciun
In a subsequent patch we will enable building security.c for Book3E. However the NXP platforms are not vulnerable to Meltdown, so make the Meltdown vulnerability reporting PPC_BOOK3S_64 specific. Signed-off-by: Diana Craciun <diana.craciun@nxp.com> [mpe: Split out of larger patch] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-08-08powerpc/64: Make stf barrier PPC_BOOK3S_64 specific.Diana Craciun
NXP Book3E platforms are not vulnerable to speculative store bypass, so make the mitigations PPC_BOOK3S_64 specific. Signed-off-by: Diana Craciun <diana.craciun@nxp.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-08-07powerpc/64: Disable the speculation barrier from the command lineDiana Craciun
The speculation barrier can be disabled from the command line with the parameter: "nospectre_v1". Signed-off-by: Diana Craciun <diana.craciun@nxp.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-24powerpc64s: Show ori31 availability in spectre_v1 sysfs file not v2Michael Ellerman
When I added the spectre_v2 information in sysfs, I included the availability of the ori31 speculation barrier. Although the ori31 barrier can be used to mitigate v2, it's primarily intended as a spectre v1 mitigation. Spectre v2 is mitigated by hardware changes. So rework the sysfs files to show the ori31 information in the spectre_v1 file, rather than v2. Currently we display eg: $ grep . spectre_v* spectre_v1:Mitigation: __user pointer sanitization spectre_v2:Mitigation: Indirect branch cache disabled, ori31 speculation barrier enabled After: $ grep . spectre_v* spectre_v1:Mitigation: __user pointer sanitization, ori31 speculation barrier enabled spectre_v2:Mitigation: Indirect branch cache disabled Fixes: d6fbe1c55c55 ("powerpc/64s: Wire up cpu_show_spectre_v2()") Cc: stable@vger.kernel.org # v4.17+ Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-07Merge tag 'powerpc-4.18-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Notable changes: - Support for split PMD page table lock on 64-bit Book3S (Power8/9). - Add support for HAVE_RELIABLE_STACKTRACE, so we properly support live patching again. - Add support for patching barrier_nospec in copy_from_user() and syscall entry. - A couple of fixes for our data breakpoints on Book3S. - A series from Nick optimising TLB/mm handling with the Radix MMU. - Numerous small cleanups to squash sparse/gcc warnings from Mathieu Malaterre. - Several series optimising various parts of the 32-bit code from Christophe Leroy. - Removal of support for two old machines, "SBC834xE" and "C2K" ("GEFanuc,C2K"), which is why the diffstat has so many deletions. And many other small improvements & fixes. There's a few out-of-area changes. Some minor ftrace changes OK'ed by Steve, and a fix to our powernv cpuidle driver. Then there's a series touching mm, x86 and fs/proc/task_mmu.c, which cleans up some details around pkey support. It was ack'ed/reviewed by Ingo & Dave and has been in next for several weeks. Thanks to: Akshay Adiga, Alastair D'Silva, Alexey Kardashevskiy, Al Viro, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Arnd Bergmann, Balbir Singh, Cédric Le Goater, Christophe Leroy, Christophe Lombard, Colin Ian King, Dave Hansen, Fabio Estevam, Finn Thain, Frederic Barrat, Gautham R. Shenoy, Haren Myneni, Hari Bathini, Ingo Molnar, Jonathan Neuschäfer, Josh Poimboeuf, Kamalesh Babulal, Madhavan Srinivasan, Mahesh Salgaonkar, Mark Greer, Mathieu Malaterre, Matthew Wilcox, Michael Neuling, Michal Suchanek, Naveen N. Rao, Nicholas Piggin, Nicolai Stange, Olof Johansson, Paul Gortmaker, Paul Mackerras, Peter Rosin, Pridhiviraj Paidipeddi, Ram Pai, Rashmica Gupta, Ravi Bangoria, Russell Currey, Sam Bobroff, Samuel Mendoza-Jonas, Segher Boessenkool, Shilpasri G Bhat, Simon Guo, Souptick Joarder, Stewart Smith, Thiago Jung Bauermann, Torsten Duwe, Vaibhav Jain, Wei Yongjun, Wolfram Sang, Yisheng Xie, YueHaibing" * tag 'powerpc-4.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (251 commits) powerpc/64s/radix: Fix missing ptesync in flush_cache_vmap cpuidle: powernv: Fix promotion from snooze if next state disabled powerpc: fix build failure by disabling attribute-alias warning in pci_32 ocxl: Fix missing unlock on error in afu_ioctl_enable_p9_wait() powerpc-opal: fix spelling mistake "Uniterrupted" -> "Uninterrupted" powerpc: fix spelling mistake: "Usupported" -> "Unsupported" powerpc/pkeys: Detach execute_only key on !PROT_EXEC powerpc/powernv: copy/paste - Mask SO bit in CR powerpc: Remove core support for Marvell mv64x60 hostbridges powerpc/boot: Remove core support for Marvell mv64x60 hostbridges powerpc/boot: Remove support for Marvell mv64x60 i2c controller powerpc/boot: Remove support for Marvell MPSC serial controller powerpc/embedded6xx: Remove C2K board support powerpc/lib: optimise PPC32 memcmp powerpc/lib: optimise 32 bits __clear_user() powerpc/time: inline arch_vtime_task_switch() powerpc/Makefile: set -mcpu=860 flag for the 8xx powerpc: Implement csum_ipv6_magic in assembly powerpc/32: Optimise __csum_partial() powerpc/lib: Adjust .balign inside string functions for PPC32 ...
2018-06-03powerpc/64s: Enhance the information in cpu_show_spectre_v1()Michal Suchanek
We now have barrier_nospec as mitigation so print it in cpu_show_spectre_v1() when enabled. Signed-off-by: Michal Suchanek <msuchanek@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03powerpc/64s: Enable barrier_nospec based on firmware settingsMichal Suchanek
Check what firmware told us and enable/disable the barrier_nospec as appropriate. We err on the side of enabling the barrier, as it's no-op on older systems, see the comment for more detail. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03powerpc/64s: Patch barrier_nospec in modulesMichal Suchanek
Note that unlike RFI which is patched only in kernel the nospec state reflects settings at the time the module was loaded. Iterating all modules and re-patching every time the settings change is not implemented. Based on lwsync patching. Signed-off-by: Michal Suchanek <msuchanek@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03powerpc/64s: Add support for ori barrier_nospec patchingMichal Suchanek
Based on the RFI patching. This is required to be able to disable the speculation barrier. Only one barrier type is supported and it does nothing when the firmware does not enable it. Also re-patching modules is not supported So the only meaningful thing that can be done is patching out the speculation barrier at boot when the user says it is not wanted. Signed-off-by: Michal Suchanek <msuchanek@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-21powerpc/64s: Add support for a store forwarding barrier at kernel entry/exitNicholas Piggin
On some CPUs we can prevent a vulnerability related to store-to-load forwarding by preventing store forwarding between privilege domains, by inserting a barrier in kernel entry and exit paths. This is known to be the case on at least Power7, Power8 and Power9 powerpc CPUs. Barriers must be inserted generally before the first load after moving to a higher privilege, and after the last store before moving to a lower privilege, HV and PR privilege transitions must be protected. Barriers are added as patch sections, with all kernel/hypervisor entry points patched, and the exit points to lower privilge levels patched similarly to the RFI flush patching. Firmware advertisement is not implemented yet, so CPU flush types are hard coded. Thanks to Michal Suchánek for bug fixes and review. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michal Suchánek <msuchanek@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-03powerpc: Move default security feature flagsMauricio Faria de Oliveira
This moves the definition of the default security feature flags (i.e., enabled by default) closer to the security feature flags. This can be used to restore current flags to the default flags. Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-27powerpc/64s: Wire up cpu_show_spectre_v2()Michael Ellerman
Add a definition for cpu_show_spectre_v2() to override the generic version. This has several permuations, though in practice some may not occur we cater for any combination. The most verbose is: Mitigation: Indirect branch serialisation (kernel only), Indirect branch cache disabled, ori31 speculation barrier enabled We don't treat the ori31 speculation barrier as a mitigation on its own, because it has to be *used* by code in order to be a mitigation and we don't know if userspace is doing that. So if that's all we see we say: Vulnerable, ori31 speculation barrier enabled Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-27powerpc/64s: Wire up cpu_show_spectre_v1()Michael Ellerman
Add a definition for cpu_show_spectre_v1() to override the generic version. Currently this just prints "Not affected" or "Vulnerable" based on the firmware flag. Although the kernel does have array_index_nospec() in a few places, we haven't yet audited all the powerpc code to see where it's necessary, so for now we don't list that as a mitigation. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-27powerpc/64s: Enhance the information in cpu_show_meltdown()Michael Ellerman
Now that we have the security feature flags we can make the information displayed in the "meltdown" file more informative. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-27powerpc/64s: Move cpu_show_meltdown()Michael Ellerman
This landed in setup_64.c for no good reason other than we had nowhere else to put it. Now that we have a security-related file, that is a better place for it so move it. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-27powerpc: Add security feature flags for Spectre/MeltdownMichael Ellerman
This commit adds security feature flags to reflect the settings we receive from firmware regarding Spectre/Meltdown mitigations. The feature names reflect the names we are given by firmware on bare metal machines. See the hostboot source for details. Arguably these could be firmware features, but that then requires them to be read early in boot so they're available prior to asm feature patching, but we don't actually want to use them for patching. We may also want to dynamically update them in future, which would be incompatible with the way firmware features work (at the moment at least). So for now just make them separate flags. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>