# git rev-parse -q --verify 958f338e96f874a0d29442396d6adf9c1e17aa2d^{commit} 958f338e96f874a0d29442396d6adf9c1e17aa2d already have revision, skipping fetch # git checkout -q -f -B kisskb 958f338e96f874a0d29442396d6adf9c1e17aa2d # git clean -qxdf # < git log -1 # commit 958f338e96f874a0d29442396d6adf9c1e17aa2d # Merge: 781fca5 07d981a # Author: Linus Torvalds # Date: Tue Aug 14 09:46:06 2018 -0700 # # Merge branch 'l1tf-final' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip # # Merge L1 Terminal Fault fixes from Thomas Gleixner: # "L1TF, aka L1 Terminal Fault, is yet another speculative hardware # engineering trainwreck. It's a hardware vulnerability which allows # unprivileged speculative access to data which is available in the # Level 1 Data Cache when the page table entry controlling the virtual # address, which is used for the access, has the Present bit cleared or # other reserved bits set. # # If an instruction accesses a virtual address for which the relevant # page table entry (PTE) has the Present bit cleared or other reserved # bits set, then speculative execution ignores the invalid PTE and loads # the referenced data if it is present in the Level 1 Data Cache, as if # the page referenced by the address bits in the PTE was still present # and accessible. # # While this is a purely speculative mechanism and the instruction will # raise a page fault when it is retired eventually, the pure act of # loading the data and making it available to other speculative # instructions opens up the opportunity for side channel attacks to # unprivileged malicious code, similar to the Meltdown attack. # # While Meltdown breaks the user space to kernel space protection, L1TF # allows to attack any physical memory address in the system and the # attack works across all protection domains. It allows an attack of SGX # and also works from inside virtual machines because the speculation # bypasses the extended page table (EPT) protection mechanism. # # The assoicated CVEs are: CVE-2018-3615, CVE-2018-3620, CVE-2018-3646 # # The mitigations provided by this pull request include: # # - Host side protection by inverting the upper address bits of a non # present page table entry so the entry points to uncacheable memory. # # - Hypervisor protection by flushing L1 Data Cache on VMENTER. # # - SMT (HyperThreading) control knobs, which allow to 'turn off' SMT # by offlining the sibling CPU threads. The knobs are available on # the kernel command line and at runtime via sysfs # # - Control knobs for the hypervisor mitigation, related to L1D flush # and SMT control. The knobs are available on the kernel command line # and at runtime via sysfs # # - Extensive documentation about L1TF including various degrees of # mitigations. # # Thanks to all people who have contributed to this in various ways - # patches, review, testing, backporting - and the fruitful, sometimes # heated, but at the end constructive discussions. # # There is work in progress to provide other forms of mitigations, which # might be less horrible performance wise for a particular kind of # workloads, but this is not yet ready for consumption due to their # complexity and limitations" # # * 'l1tf-final' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (75 commits) # x86/microcode: Allow late microcode loading with SMT disabled # tools headers: Synchronise x86 cpufeatures.h for L1TF additions # x86/mm/kmmio: Make the tracer robust against L1TF # x86/mm/pat: Make set_memory_np() L1TF safe # x86/speculation/l1tf: Make pmd/pud_mknotpresent() invert # x86/speculation/l1tf: Invert all not present mappings # cpu/hotplug: Fix SMT supported evaluation # KVM: VMX: Tell the nested hypervisor to skip L1D flush on vmentry # x86/speculation: Use ARCH_CAPABILITIES to skip L1D flush on vmentry # x86/speculation: Simplify sysfs report of VMX L1TF vulnerability # Documentation/l1tf: Remove Yonah processors from not vulnerable list # x86/KVM/VMX: Don't set l1tf_flush_l1d from vmx_handle_external_intr() # x86/irq: Let interrupt handlers set kvm_cpu_l1tf_flush_l1d # x86: Don't include linux/irq.h from asm/hardirq.h # x86/KVM/VMX: Introduce per-host-cpu analogue of l1tf_flush_l1d # x86/irq: Demote irq_cpustat_t::__softirq_pending to u16 # x86/KVM/VMX: Move the l1tf_flush_l1d test to vmx_l1d_flush() # x86/KVM/VMX: Replace 'vmx_l1d_flush_always' with 'vmx_l1d_flush_cond' # x86/KVM/VMX: Don't set l1tf_flush_l1d to true from vmx_l1d_flush() # cpu/hotplug: detect SMT disabled by BIOS # ... # < /opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux-gcc --version # < git log --format=%s --max-count=1 958f338e96f874a0d29442396d6adf9c1e17aa2d # < make -s -j 120 ARCH=powerpc O=/kisskb/build/linus_44x_currituck_defconfig_powerpc CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux- 44x/currituck_defconfig # make -s -j 120 ARCH=powerpc O=/kisskb/build/linus_44x_currituck_defconfig_powerpc CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux- /kisskb/src/kernel/rcu/srcutree.c: In function 'init_srcu_struct_fields': /kisskb/src/kernel/rcu/srcutree.c:148:32: warning: 'levelspread[]' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/kernel/rcu/srcutree.c:96:6: note: 'levelspread[]' was declared here /kisskb/src/kernel/printk/printk.c: In function 'devkmsg_sysctl_set_loglvl': /kisskb/src/kernel/printk/printk.c:183:16: warning: 'old' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/proc/inode.c: In function 'proc_reg_open': /kisskb/src/include/linux/list.h:65:12: warning: 'pdeo' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/proc/inode.c:339:21: note: 'pdeo' was declared here /kisskb/src/drivers/base/regmap/regmap.c: In function 'regmap_raw_read': /kisskb/src/drivers/base/regmap/regmap.c:2497:6: warning: 'ret' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/base/regmap/regmap.c: In function '_regmap_raw_write': /kisskb/src/drivers/base/regmap/regmap.c:1819:6: warning: 'ret' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/tty/serial/8250/8250_core.c: In function 'univ8250_release_irq': /kisskb/src/drivers/tty/serial/8250/8250_core.c:251:18: warning: 'i' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/tty/serial/8250/8250_core.c:231:19: note: 'i' was declared here WARNING: modpost: Found 1 section mismatch(es). To see full details build your kernel with: 'make CONFIG_DEBUG_SECTION_MISMATCH=y' arch/powerpc/boot/currituck.dtb: Warning (pci_bridge): /plb/pciex@10100000000: node name is not "pci" or "pcie" arch/powerpc/boot/currituck.dtb: Warning (pci_bridge): /plb/pciex@30100000000: node name is not "pci" or "pcie" arch/powerpc/boot/currituck.dtb: Warning (pci_bridge): /plb/pciex@38100000000: node name is not "pci" or "pcie" arch/powerpc/boot/currituck.dtb: Warning (pci_device_bus_num): Failed prerequisite 'pci_bridge' Completed OK # rm -rf /kisskb/build/linus_44x_currituck_defconfig_powerpc # Build took: 0:00:36.815385