4.14-stable review patch. If anyone has any objections, please let me know.

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From: Andrey Ryabinin aryabinin@virtuozzo.com

commit f5a40711fa58f1c109165a4fec6078bf2dfd2bdc upstream.

Since f06bdd4001c2 ("x86/mm: Adapt MODULES_END based on fixmap section size") kasan_mem_to_shadow(MODULES_END) could be not aligned to a page boundary.

So passing page unaligned address to kasan_populate_zero_shadow() have two possible effects:

1) It may leave one page hole in supposed to be populated area. After commit 21506525fb8d ("x86/kasan/64: Teach KASAN about the cpu_entry_area") that hole happens to be in the shadow covering fixmap area and leads to crash:

BUG: unable to handle kernel paging request at fffffbffffe8ee04 RIP: 0010:check_memory_region+0x5c/0x190

Call Trace: <NMI> memcpy+0x1f/0x50 ghes_copy_tofrom_phys+0xab/0x180 ghes_read_estatus+0xfb/0x280 ghes_notify_nmi+0x2b2/0x410 nmi_handle+0x115/0x2c0 default_do_nmi+0x57/0x110 do_nmi+0xf8/0x150 end_repeat_nmi+0x1a/0x1e

Note, the crash likely disappeared after commit 92a0f81d8957, which changed kasan_populate_zero_shadow() call the way it was before commit 21506525fb8d.

2) Attempt to load module near MODULES_END will fail, because __vmalloc_node_range() called from kasan_module_alloc() will hit the WARN_ON(!pte_none(*pte)) in the vmap_pte_range() and bail out with error.

To fix this we need to make kasan_mem_to_shadow(MODULES_END) page aligned which means that MODULES_END should be 8*PAGE_SIZE aligned.

The whole point of commit f06bdd4001c2 was to move MODULES_END down if NR_CPUS is big, so the cpu_entry_area takes a lot of space. But since 92a0f81d8957 ("x86/cpu_entry_area: Move it out of the fixmap") the cpu_entry_area is no longer in fixmap, so we could just set MODULES_END to a fixed 8*PAGE_SIZE aligned address.

Fixes: f06bdd4001c2 ("x86/mm: Adapt MODULES_END based on fixmap section size") Reported-by: Jakub Kicinski kubakici@wp.pl Signed-off-by: Andrey Ryabinin aryabinin@virtuozzo.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Cc: Andy Lutomirski luto@kernel.org Cc: Thomas Garnier thgarnie@google.com Link: https://lkml.kernel.org/r/20171228160620.23818-1-aryabinin@virtuozzo.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- Documentation/x86/x86_64/mm.txt | 5 +---- arch/x86/include/asm/pgtable_64_types.h | 2 +- 2 files changed, 2 insertions(+), 5 deletions(-)

--- a/Documentation/x86/x86_64/mm.txt +++ b/Documentation/x86/x86_64/mm.txt @@ -43,7 +43,7 @@ ffffff0000000000 - ffffff7fffffffff (=39 ffffffef00000000 - fffffffeffffffff (=64 GB) EFI region mapping space ... unused hole ... ffffffff80000000 - ffffffff9fffffff (=512 MB) kernel text mapping, from phys 0 -ffffffffa0000000 - [fixmap start] (~1526 MB) module mapping space +ffffffffa0000000 - fffffffffeffffff (1520 MB) module mapping space [fixmap start] - ffffffffff5fffff kernel-internal fixmap range ffffffffff600000 - ffffffffff600fff (=4 kB) legacy vsyscall ABI ffffffffffe00000 - ffffffffffffffff (=2 MB) unused hole @@ -67,9 +67,6 @@ memory window (this size is arbitrary, i The mappings are not part of any other kernel PGD and are only available during EFI runtime calls.

-The module mapping space size changes based on the CONFIG requirements for the -following fixmap section. - Note that if CONFIG_RANDOMIZE_MEMORY is enabled, the direct mapping of all physical memory, vmalloc/ioremap space and virtual memory map are randomized. Their order is preserved but their base will be offset early at boot time. --- a/arch/x86/include/asm/pgtable_64_types.h +++ b/arch/x86/include/asm/pgtable_64_types.h @@ -104,7 +104,7 @@ typedef struct { pteval_t pte; } pte_t;

#define MODULES_VADDR (__START_KERNEL_map + KERNEL_IMAGE_SIZE) /* The module sections ends with the start of the fixmap */ -#define MODULES_END __fix_to_virt(__end_of_fixed_addresses + 1) +#define MODULES_END _AC(0xffffffffff000000, UL) #define MODULES_LEN (MODULES_END - MODULES_VADDR)

#define ESPFIX_PGD_ENTRY _AC(-2, UL)

4.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Thomas Gleixner tglx@linutronix.de

commit 1dddd25125112ba49706518ac9077a1026a18f37 upstream.

vaddr_end for KASLR is only documented in the KASLR code itself and is adjusted depending on config options. So it's not surprising that a change of the memory layout causes KASLR to have the wrong vaddr_end. This can map arbitrary stuff into other areas causing hard to understand problems.

Remove the whole ifdef magic and define the start of the cpu_entry_area to be the end of the KASLR vaddr range.

Add documentation to that effect.

Fixes: 92a0f81d8957 ("x86/cpu_entry_area: Move it out of the fixmap") Reported-by: Benjamin Gilbert benjamin.gilbert@coreos.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Tested-by: Benjamin Gilbert benjamin.gilbert@coreos.com Cc: Andy Lutomirski luto@kernel.org Cc: Greg Kroah-Hartman gregkh@linuxfoundation.org Cc: Dave Hansen dave.hansen@linux.intel.com Cc: Peter Zijlstra peterz@infradead.org Cc: Thomas Garnier thgarnie@google.com Cc: Alexander Kuleshov kuleshovmail@gmail.com Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801041320360.1771@nanos Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- Documentation/x86/x86_64/mm.txt | 6 ++++++ arch/x86/include/asm/pgtable_64_types.h | 8 +++++++- arch/x86/mm/kaslr.c | 32 +++++++++----------------------- 3 files changed, 22 insertions(+), 24 deletions(-)

--- a/Documentation/x86/x86_64/mm.txt +++ b/Documentation/x86/x86_64/mm.txt @@ -12,6 +12,7 @@ ffffea0000000000 - ffffeaffffffffff (=40 ... unused hole ... ffffec0000000000 - fffffbffffffffff (=44 bits) kasan shadow memory (16TB) ... unused hole ... + vaddr_end for KASLR fffffe0000000000 - fffffe7fffffffff (=39 bits) cpu_entry_area mapping fffffe8000000000 - fffffeffffffffff (=39 bits) LDT remap for PTI ffffff0000000000 - ffffff7fffffffff (=39 bits) %esp fixup stacks @@ -37,6 +38,7 @@ ffd4000000000000 - ffd5ffffffffffff (=49 ... unused hole ... ffdf000000000000 - fffffc0000000000 (=53 bits) kasan shadow memory (8PB) ... unused hole ... + vaddr_end for KASLR fffffe0000000000 - fffffe7fffffffff (=39 bits) cpu_entry_area mapping ... unused hole ... ffffff0000000000 - ffffff7fffffffff (=39 bits) %esp fixup stacks @@ -71,3 +73,7 @@ during EFI runtime calls. Note that if CONFIG_RANDOMIZE_MEMORY is enabled, the direct mapping of all physical memory, vmalloc/ioremap space and virtual memory map are randomized. Their order is preserved but their base will be offset early at boot time. + +Be very careful vs. KASLR when changing anything here. The KASLR address +range must not overlap with anything except the KASAN shadow area, which is +correct as KASAN disables KASLR. --- a/arch/x86/include/asm/pgtable_64_types.h +++ b/arch/x86/include/asm/pgtable_64_types.h @@ -75,7 +75,13 @@ typedef struct { pteval_t pte; } pte_t; #define PGDIR_SIZE (_AC(1, UL) << PGDIR_SHIFT) #define PGDIR_MASK (~(PGDIR_SIZE - 1))

-/* See Documentation/x86/x86_64/mm.txt for a description of the memory map. */ +/* + * See Documentation/x86/x86_64/mm.txt for a description of the memory map. + * + * Be very careful vs. KASLR when changing anything here. The KASLR address + * range must not overlap with anything except the KASAN shadow area, which + * is correct as KASAN disables KASLR. + */ #define MAXMEM _AC(__AC(1, UL) << MAX_PHYSMEM_BITS, UL)

#ifdef CONFIG_X86_5LEVEL --- a/arch/x86/mm/kaslr.c +++ b/arch/x86/mm/kaslr.c @@ -34,25 +34,14 @@ #define TB_SHIFT 40

/* - * Virtual address start and end range for randomization. The end changes base - * on configuration to have the highest amount of space for randomization. - * It increases the possible random position for each randomized region. + * Virtual address start and end range for randomization. * - * You need to add an if/def entry if you introduce a new memory region - * compatible with KASLR. Your entry must be in logical order with memory - * layout. For example, ESPFIX is before EFI because its virtual address is - * before. You also need to add a BUILD_BUG_ON() in kernel_randomize_memory() to - * ensure that this order is correct and won't be changed. + * The end address could depend on more configuration options to make the + * highest amount of space for randomization available, but that's too hard + * to keep straight and caused issues already. */ static const unsigned long vaddr_start = __PAGE_OFFSET_BASE; - -#if defined(CONFIG_X86_ESPFIX64) -static const unsigned long vaddr_end = ESPFIX_BASE_ADDR; -#elif defined(CONFIG_EFI) -static const unsigned long vaddr_end = EFI_VA_END; -#else -static const unsigned long vaddr_end = __START_KERNEL_map; -#endif +static const unsigned long vaddr_end = CPU_ENTRY_AREA_BASE;

/* Default values */ unsigned long page_offset_base = __PAGE_OFFSET_BASE; @@ -101,15 +90,12 @@ void __init kernel_randomize_memory(void unsigned long remain_entropy;

/* - * All these BUILD_BUG_ON checks ensures the memory layout is - * consistent with the vaddr_start/vaddr_end variables. + * These BUILD_BUG_ON checks ensure the memory layout is consistent + * with the vaddr_start/vaddr_end variables. These checks are very + * limited.... */ BUILD_BUG_ON(vaddr_start >= vaddr_end); - BUILD_BUG_ON(IS_ENABLED(CONFIG_X86_ESPFIX64) && - vaddr_end >= EFI_VA_END); - BUILD_BUG_ON((IS_ENABLED(CONFIG_X86_ESPFIX64) || - IS_ENABLED(CONFIG_EFI)) && - vaddr_end >= __START_KERNEL_map); + BUILD_BUG_ON(vaddr_end != CPU_ENTRY_AREA_BASE); BUILD_BUG_ON(vaddr_end > __START_KERNEL_map);

if (!kaslr_memory_enabled())

4.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Thomas Gleixner tglx@linutronix.de

commit 1e5476815fd7f98b888e01a0f9522b63085f96c9 upstream.

The recent changes for PTI touch cpu_tlbstate from various tlb_flush inlines. cpu_tlbstate is exported as GPL symbol, so this causes a regression when building out of tree drivers for certain graphics cards.

Aside of that the export was wrong since it was introduced as it should have been EXPORT_PER_CPU_SYMBOL_GPL().

Use the correct PER_CPU export and drop the _GPL to restore the previous state which allows users to utilize the cards they payed for.

As always I'm really thrilled to make this kind of change to support the #friends (or however the hot hashtag of today is spelled) from that closet sauce graphics corp.

Fixes: 1e02ce4cccdc ("x86: Store a per-cpu shadow copy of CR4") Fixes: 6fd166aae78c ("x86/mm: Use/Fix PCID to optimize user/kernel switches") Reported-by: Kees Cook keescook@google.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Cc: Greg Kroah-Hartman gregkh@linuxfoundation.org Cc: Peter Zijlstra peterz@infradead.org Cc: Andy Lutomirski luto@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- arch/x86/mm/init.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -870,7 +870,7 @@ __visible DEFINE_PER_CPU_SHARED_ALIGNED( .next_asid = 1, .cr4 = ~0UL, /* fail hard if we screw up cr4 shadow initialization */ }; -EXPORT_SYMBOL_GPL(cpu_tlbstate); +EXPORT_PER_CPU_SYMBOL(cpu_tlbstate);

void update_cache_mode_entry(unsigned entry, enum page_cache_mode cache) {

4.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Thomas Gleixner tglx@linutronix.de

commit de791821c295cc61419a06fe5562288417d1bc58 upstream.

Use the name associated with the particular attack which needs page table isolation for mitigation.

Signed-off-by: Thomas Gleixner tglx@linutronix.de Acked-by: David Woodhouse dwmw@amazon.co.uk Cc: Alan Cox gnomes@lxorguk.ukuu.org.uk Cc: Jiri Koshina jikos@kernel.org Cc: Linus Torvalds torvalds@linux-foundation.org Cc: Tim Chen tim.c.chen@linux.intel.com Cc: Andi Lutomirski luto@amacapital.net Cc: Andi Kleen ak@linux.intel.com Cc: Peter Zijlstra peterz@infradead.org Cc: Paul Turner pjt@google.com Cc: Tom Lendacky thomas.lendacky@amd.com Cc: Greg KH gregkh@linux-foundation.org Cc: Dave Hansen dave.hansen@intel.com Cc: Kees Cook keescook@google.com Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801051525300.1724@nanos Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- arch/x86/include/asm/cpufeatures.h | 2 +- arch/x86/kernel/cpu/common.c | 2 +- arch/x86/mm/pti.c | 6 +++--- 3 files changed, 5 insertions(+), 5 deletions(-)

--- a/arch/x86/include/asm/cpufeatures.h +++ b/arch/x86/include/asm/cpufeatures.h @@ -341,6 +341,6 @@ #define X86_BUG_SWAPGS_FENCE X86_BUG(11) /* SWAPGS without input dep on GS */ #define X86_BUG_MONITOR X86_BUG(12) /* IPI required to wake up remote CPU */ #define X86_BUG_AMD_E400 X86_BUG(13) /* CPU is among the affected by Erratum 400 */ -#define X86_BUG_CPU_INSECURE X86_BUG(14) /* CPU is insecure and needs kernel page table isolation */ +#define X86_BUG_CPU_MELTDOWN X86_BUG(14) /* CPU is affected by meltdown attack and needs kernel page table isolation */

#endif /* _ASM_X86_CPUFEATURES_H */ --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -900,7 +900,7 @@ static void __init early_identify_cpu(st setup_force_cpu_cap(X86_FEATURE_ALWAYS);

if (c->x86_vendor != X86_VENDOR_AMD) - setup_force_cpu_bug(X86_BUG_CPU_INSECURE); + setup_force_cpu_bug(X86_BUG_CPU_MELTDOWN);

fpu__init_system(c);

--- a/arch/x86/mm/pti.c +++ b/arch/x86/mm/pti.c @@ -56,13 +56,13 @@

static void __init pti_print_if_insecure(const char *reason) { - if (boot_cpu_has_bug(X86_BUG_CPU_INSECURE)) + if (boot_cpu_has_bug(X86_BUG_CPU_MELTDOWN)) pr_info("%s\n", reason); }

static void __init pti_print_if_secure(const char *reason) { - if (!boot_cpu_has_bug(X86_BUG_CPU_INSECURE)) + if (!boot_cpu_has_bug(X86_BUG_CPU_MELTDOWN)) pr_info("%s\n", reason); }

@@ -96,7 +96,7 @@ void __init pti_check_boottime_disable(v }

autosel: - if (!boot_cpu_has_bug(X86_BUG_CPU_INSECURE)) + if (!boot_cpu_has_bug(X86_BUG_CPU_MELTDOWN)) return; enable: setup_force_cpu_cap(X86_FEATURE_PTI);

4.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Anshuman Khandual khandual@linux.vnet.ibm.com

commit 4991c09c7c812dba13ea9be79a68b4565bb1fa4e upstream.

While testing on a large CPU system, detected the following RCU stall many times over the span of the workload. This problem is solved by adding a cond_resched() in the change_pmd_range() function.

INFO: rcu_sched detected stalls on CPUs/tasks: 154-....: (670 ticks this GP) idle=022/140000000000000/0 softirq=2825/2825 fqs=612 (detected by 955, t=6002 jiffies, g=4486, c=4485, q=90864) Sending NMI from CPU 955 to CPUs 154: NMI backtrace for cpu 154 CPU: 154 PID: 147071 Comm: workload Not tainted 4.15.0-rc3+ #3 NIP: c0000000000b3f64 LR: c0000000000b33d4 CTR: 000000000000aa18 REGS: 00000000a4b0fb44 TRAP: 0501 Not tainted (4.15.0-rc3+) MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE> CR: 22422082 XER: 00000000 CFAR: 00000000006cf8f0 SOFTE: 1 GPR00: 0010000000000000 c00003ef9b1cb8c0 c0000000010cc600 0000000000000000 GPR04: 8e0000018c32b200 40017b3858fd6e00 8e0000018c32b208 40017b3858fd6e00 GPR08: 8e0000018c32b210 40017b3858fd6e00 8e0000018c32b218 40017b3858fd6e00 GPR12: ffffffffffffffff c00000000fb25100 NIP [c0000000000b3f64] plpar_hcall9+0x44/0x7c LR [c0000000000b33d4] pSeries_lpar_flush_hash_range+0x384/0x420 Call Trace: flush_hash_range+0x48/0x100 __flush_tlb_pending+0x44/0xd0 hpte_need_flush+0x408/0x470 change_protection_range+0xaac/0xf10 change_prot_numa+0x30/0xb0 task_numa_work+0x2d0/0x3e0 task_work_run+0x130/0x190 do_notify_resume+0x118/0x120 ret_from_except_lite+0x70/0x74 Instruction dump: 60000000 f8810028 7ca42b78 7cc53378 7ce63b78 7d074378 7d284b78 7d495378 e9410060 e9610068 e9810070 44000022 <7d806378> e9810028 f88c0000 f8ac0008

Link: http://lkml.kernel.org/r/20171214140551.5794-1-khandual@linux.vnet.ibm.com Signed-off-by: Anshuman Khandual khandual@linux.vnet.ibm.com Suggested-by: Nicholas Piggin npiggin@gmail.com Acked-by: Michal Hocko mhocko@suse.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- mm/mprotect.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)

--- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -166,7 +166,7 @@ static inline unsigned long change_pmd_r next = pmd_addr_end(addr, end); if (!is_swap_pmd(*pmd) && !pmd_trans_huge(*pmd) && !pmd_devmap(*pmd) && pmd_none_or_clear_bad(pmd)) - continue; + goto next;

/* invoke the mmu notifier if the pmd is populated */ if (!mni_start) { @@ -188,7 +188,7 @@ static inline unsigned long change_pmd_r }

/* huge pmd was handled */ - continue; + goto next; } } /* fall through, the trans huge pmd just split */ @@ -196,6 +196,8 @@ static inline unsigned long change_pmd_r this_pages = change_pte_range(vma, pmd, addr, next, newprot, dirty_accountable, prot_numa); pages += this_pages; +next: + cond_resched(); } while (pmd++, addr = next, addr != end);

if (mni_start)

4.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Andrea Arcangeli aarcange@redhat.com

commit 0cbb4b4f4c44f54af268969b18d8deda63aded59 upstream.

The previous fix in commit 384632e67e08 ("userfaultfd: non-cooperative: fix fork use after free") corrected the refcounting in case of UFFD_EVENT_FORK failure for the fork userfault paths.

That still didn't clear the vma->vm_userfaultfd_ctx of the vmas that were set to point to the aborted new uffd ctx earlier in dup_userfaultfd.

Link: http://lkml.kernel.org/r/20171223002505.593-2-aarcange@redhat.com Signed-off-by: Andrea Arcangeli aarcange@redhat.com Reported-by: syzbot syzkaller@googlegroups.com Reviewed-by: Mike Rapoport rppt@linux.vnet.ibm.com Cc: Eric Biggers ebiggers3@gmail.com Cc: Dmitry Vyukov dvyukov@google.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- fs/userfaultfd.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-)

--- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -570,11 +570,14 @@ out: static void userfaultfd_event_wait_completion(struct userfaultfd_ctx *ctx, struct userfaultfd_wait_queue *ewq) { + struct userfaultfd_ctx *release_new_ctx; + if (WARN_ON_ONCE(current->flags & PF_EXITING)) goto out;

ewq->ctx = ctx; init_waitqueue_entry(&ewq->wq, current); + release_new_ctx = NULL;

spin_lock(&ctx->event_wqh.lock); /* @@ -601,8 +604,7 @@ static void userfaultfd_event_wait_compl new = (struct userfaultfd_ctx *) (unsigned long) ewq->msg.arg.reserved.reserved1; - - userfaultfd_ctx_put(new); + release_new_ctx = new; } break; } @@ -617,6 +619,20 @@ static void userfaultfd_event_wait_compl __set_current_state(TASK_RUNNING); spin_unlock(&ctx->event_wqh.lock);

+ if (release_new_ctx) { + struct vm_area_struct *vma; + struct mm_struct *mm = release_new_ctx->mm; + + /* the various vma->vm_userfaultfd_ctx still points to it */ + down_write(&mm->mmap_sem); + for (vma = mm->mmap; vma; vma = vma->vm_next) + if (vma->vm_userfaultfd_ctx.ctx == release_new_ctx) + vma->vm_userfaultfd_ctx = NULL_VM_UFFD_CTX; + up_write(&mm->mmap_sem); + + userfaultfd_ctx_put(release_new_ctx); + } + /* * ctx may go away after this if the userfault pseudo fd is * already released.

4.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Ard Biesheuvel ard.biesheuvel@linaro.org

commit f24c4d478013d82bd1b943df566fff3561d52864 upstream.

Commit:

82c3768b8d68 ("efi/capsule-loader: Use a cached copy of the capsule header")

... refactored the capsule loading code that maps the capsule header, to avoid having to map it several times.

However, as it turns out, the vmap() call we ended up removing did not just map the header, but the entire capsule image, and dropping this virtual mapping breaks capsules that are processed by the firmware immediately (i.e., without a reboot).

Unfortunately, that change was part of a larger refactor that allowed a quirk to be implemented for Quark, which has a non-standard memory layout for capsules, and we have slightly painted ourselves into a corner by allowing quirk code to mangle the capsule header and memory layout.

So we need to fix this without breaking Quark. Fortunately, Quark does not appear to care about the virtual mapping, and so we can simply do a partial revert of commit:

2a457fb31df6 ("efi/capsule-loader: Use page addresses rather than struct page pointers")

... and create a vmap() mapping of the entire capsule (including header) based on the reinstated struct page array, unless running on Quark, in which case we pass the capsule header copy as before.

Reported-by: Ge Song ge.song@hxt-semitech.com Tested-by: Bryan O'Donoghue pure.logic@nexus-software.ie Tested-by: Ge Song ge.song@hxt-semitech.com Signed-off-by: Ard Biesheuvel ard.biesheuvel@linaro.org Cc: Dave Young dyoung@redhat.com Cc: Linus Torvalds torvalds@linux-foundation.org Cc: Matt Fleming matt@codeblueprint.co.uk Cc: Peter Zijlstra peterz@infradead.org Cc: Thomas Gleixner tglx@linutronix.de Cc: linux-efi@vger.kernel.org Fixes: 82c3768b8d68 ("efi/capsule-loader: Use a cached copy of the capsule header") Link: http://lkml.kernel.org/r/20180102172110.17018-3-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar mingo@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- arch/x86/platform/efi/quirks.c | 13 +++++++++ drivers/firmware/efi/capsule-loader.c | 45 +++++++++++++++++++++++++++------- include/linux/efi.h | 4 ++- 3 files changed, 52 insertions(+), 10 deletions(-)

--- a/arch/x86/platform/efi/quirks.c +++ b/arch/x86/platform/efi/quirks.c @@ -592,7 +592,18 @@ static int qrk_capsule_setup_info(struct /* * Update the first page pointer to skip over the CSH header. */ - cap_info->pages[0] += csh->headersize; + cap_info->phys[0] += csh->headersize; + + /* + * cap_info->capsule should point at a virtual mapping of the entire + * capsule, starting at the capsule header. Our image has the Quark + * security header prepended, so we cannot rely on the default vmap() + * mapping created by the generic capsule code. + * Given that the Quark firmware does not appear to care about the + * virtual mapping, let's just point cap_info->capsule at our copy + * of the capsule header. + */ + cap_info->capsule = &cap_info->header;

return 1; } --- a/drivers/firmware/efi/capsule-loader.c +++ b/drivers/firmware/efi/capsule-loader.c @@ -20,10 +20,6 @@

#define NO_FURTHER_WRITE_ACTION -1

-#ifndef phys_to_page -#define phys_to_page(x) pfn_to_page((x) >> PAGE_SHIFT) -#endif - /** * efi_free_all_buff_pages - free all previous allocated buffer pages * @cap_info: pointer to current instance of capsule_info structure @@ -35,7 +31,7 @@ static void efi_free_all_buff_pages(struct capsule_info *cap_info) { while (cap_info->index > 0) - __free_page(phys_to_page(cap_info->pages[--cap_info->index])); + __free_page(cap_info->pages[--cap_info->index]);

cap_info->index = NO_FURTHER_WRITE_ACTION; } @@ -71,6 +67,14 @@ int __efi_capsule_setup_info(struct caps

cap_info->pages = temp_page;

+ temp_page = krealloc(cap_info->phys, + pages_needed * sizeof(phys_addr_t *), + GFP_KERNEL | __GFP_ZERO); + if (!temp_page) + return -ENOMEM; + + cap_info->phys = temp_page; + return 0; }

@@ -105,9 +109,24 @@ int __weak efi_capsule_setup_info(struct **/ static ssize_t efi_capsule_submit_update(struct capsule_info *cap_info) { + bool do_vunmap = false; int ret;

- ret = efi_capsule_update(&cap_info->header, cap_info->pages); + /* + * cap_info->capsule may have been assigned already by a quirk + * handler, so only overwrite it if it is NULL + */ + if (!cap_info->capsule) { + cap_info->capsule = vmap(cap_info->pages, cap_info->index, + VM_MAP, PAGE_KERNEL); + if (!cap_info->capsule) + return -ENOMEM; + do_vunmap = true; + } + + ret = efi_capsule_update(cap_info->capsule, cap_info->phys); + if (do_vunmap) + vunmap(cap_info->capsule); if (ret) { pr_err("capsule update failed\n"); return ret; @@ -165,10 +184,12 @@ static ssize_t efi_capsule_write(struct goto failed; }

- cap_info->pages[cap_info->index++] = page_to_phys(page); + cap_info->pages[cap_info->index] = page; + cap_info->phys[cap_info->index] = page_to_phys(page); cap_info->page_bytes_remain = PAGE_SIZE; + cap_info->index++; } else { - page = phys_to_page(cap_info->pages[cap_info->index - 1]); + page = cap_info->pages[cap_info->index - 1]; }

kbuff = kmap(page); @@ -252,6 +273,7 @@ static int efi_capsule_release(struct in struct capsule_info *cap_info = file->private_data;

kfree(cap_info->pages); + kfree(cap_info->phys); kfree(file->private_data); file->private_data = NULL; return 0; @@ -280,6 +302,13 @@ static int efi_capsule_open(struct inode kfree(cap_info); return -ENOMEM; } + + cap_info->phys = kzalloc(sizeof(void *), GFP_KERNEL); + if (!cap_info->phys) { + kfree(cap_info->pages); + kfree(cap_info); + return -ENOMEM; + }

file->private_data = cap_info;

--- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -140,11 +140,13 @@ struct efi_boot_memmap {

struct capsule_info { efi_capsule_header_t header; + efi_capsule_header_t *capsule; int reset_type; long index; size_t count; size_t total_size; - phys_addr_t *pages; + struct page **pages; + phys_addr_t *phys; size_t page_bytes_remain; };

4.14-stable review patch. If anyone has any objections, please let me know.

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From: Eric Biggers ebiggers@google.com

commit e57121d08c38dabec15cf3e1e2ad46721af30cae upstream.

If the rfc7539 template was instantiated with a hash algorithm with digest size larger than 16 bytes (POLY1305_DIGEST_SIZE), then the digest overran the 'tag' buffer in 'struct chachapoly_req_ctx', corrupting the subsequent memory, including 'cryptlen'. This caused a crash during crypto_skcipher_decrypt().

Fix it by, when instantiating the template, requiring that the underlying hash algorithm has the digest size expected for Poly1305.

Reproducer:

#include <linux/if_alg.h> #include <sys/socket.h> #include <unistd.h>

int main() { int algfd, reqfd; struct sockaddr_alg addr = { .salg_type = "aead", .salg_name = "rfc7539(chacha20,sha256)", }; unsigned char buf[32] = { 0 };

algfd = socket(AF_ALG, SOCK_SEQPACKET, 0); bind(algfd, (void *)&addr, sizeof(addr)); setsockopt(algfd, SOL_ALG, ALG_SET_KEY, buf, sizeof(buf)); reqfd = accept(algfd, 0, 0); write(reqfd, buf, 16); read(reqfd, buf, 16); }

Reported-by: syzbot syzkaller@googlegroups.com Fixes: 71ebc4d1b27d ("crypto: chacha20poly1305 - Add a ChaCha20-Poly1305 AEAD construction, RFC7539") Signed-off-by: Eric Biggers ebiggers@google.com Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- crypto/chacha20poly1305.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)

--- a/crypto/chacha20poly1305.c +++ b/crypto/chacha20poly1305.c @@ -610,6 +610,11 @@ static int chachapoly_create(struct cryp algt->mask)); if (IS_ERR(poly)) return PTR_ERR(poly); + poly_hash = __crypto_hash_alg_common(poly); + + err = -EINVAL; + if (poly_hash->digestsize != POLY1305_DIGEST_SIZE) + goto out_put_poly;

err = -ENOMEM; inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL); @@ -618,7 +623,6 @@ static int chachapoly_create(struct cryp

ctx = aead_instance_ctx(inst); ctx->saltlen = CHACHAPOLY_IV_SIZE - ivsize; - poly_hash = __crypto_hash_alg_common(poly); err = crypto_init_ahash_spawn(&ctx->poly, poly_hash, aead_crypto_instance(inst)); if (err)

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From: Arnd Bergmann arnd@arndb.de

commit d042566d8c704e1ecec370300545d4a409222e39 upstream.

Without the gf128mul library support, we can run into a link error:

drivers/crypto/chelsio/chcr_algo.o: In function `chcr_update_tweak': chcr_algo.c:(.text+0x7e0): undefined reference to `gf128mul_x8_ble'

This adds a Kconfig select statement for it, next to the ones we already have.

Fixes: b8fd1f4170e7 ("crypto: chcr - Add ctr mode and process large sg entries for cipher") Signed-off-by: Arnd Bergmann arnd@arndb.de Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- drivers/crypto/chelsio/Kconfig | 1 + 1 file changed, 1 insertion(+)

--- a/drivers/crypto/chelsio/Kconfig +++ b/drivers/crypto/chelsio/Kconfig @@ -5,6 +5,7 @@ config CRYPTO_DEV_CHELSIO select CRYPTO_SHA256 select CRYPTO_SHA512 select CRYPTO_AUTHENC + select CRYPTO_GF128MUL ---help--- The Chelsio Crypto Co-processor driver for T6 adapters.

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From: Rafael J. Wysocki rafael.j.wysocki@intel.com

commit b29c6ef7bb1257853c1e31616d84f55e561cf631 upstream.

Even though aperfmperf_snapshot_khz() caches the samples.khz value to return if called again in a sufficiently short time, its caller, arch_freq_get_on_cpu(), still uses smp_call_function_single() to run it which may allow user space to trigger an IPI storm by reading from the scaling_cur_freq cpufreq sysfs file in a tight loop.

To avoid that, move the decision on whether or not to return the cached samples.khz value to arch_freq_get_on_cpu().

This change was part of commit 941f5f0f6ef5 ("x86: CPU: Fix up "cpu MHz" in /proc/cpuinfo"), but it was not the reason for the revert and it remains applicable.

Fixes: 4815d3c56d1e (cpufreq: x86: Make scaling_cur_freq behave more as expected) Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Reviewed-by: WANG Chao chao.wang@ucloud.cn Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- arch/x86/kernel/cpu/aperfmperf.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-)

--- a/arch/x86/kernel/cpu/aperfmperf.c +++ b/arch/x86/kernel/cpu/aperfmperf.c @@ -42,10 +42,6 @@ static void aperfmperf_snapshot_khz(void s64 time_delta = ktime_ms_delta(now, s->time); unsigned long flags;

- /* Don't bother re-computing within the cache threshold time. */ - if (time_delta < APERFMPERF_CACHE_THRESHOLD_MS) - return; - local_irq_save(flags); rdmsrl(MSR_IA32_APERF, aperf); rdmsrl(MSR_IA32_MPERF, mperf); @@ -74,6 +70,7 @@ static void aperfmperf_snapshot_khz(void

unsigned int arch_freq_get_on_cpu(int cpu) { + s64 time_delta; unsigned int khz;

if (!cpu_khz) @@ -82,6 +79,12 @@ unsigned int arch_freq_get_on_cpu(int cp if (!static_cpu_has(X86_FEATURE_APERFMPERF)) return 0;

+ /* Don't bother re-computing within the cache threshold time. */ + time_delta = ktime_ms_delta(ktime_get(), per_cpu(samples.time, cpu)); + khz = per_cpu(samples.khz, cpu); + if (khz && time_delta < APERFMPERF_CACHE_THRESHOLD_MS) + return khz; + smp_call_function_single(cpu, aperfmperf_snapshot_khz, NULL, 1); khz = per_cpu(samples.khz, cpu); if (khz)

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From: Oleg Nesterov oleg@redhat.com

commit 628c1bcba204052d19b686b5bac149a644cdb72e upstream.

The comment in sig_ignored() says "Tracers may want to know about even ignored signals" but SIGKILL can not be reported to debugger and it is just wrong to return 0 in this case: SIGKILL should only kill the SIGNAL_UNKILLABLE task if it comes from the parent ns.

Change sig_ignored() to ignore ->ptrace if sig == SIGKILL and rely on sig_task_ignored().

SISGTOP coming from within the namespace is not really right too but at least debugger can intercept it, and we can't drop it here because this will break "gdb -p 1": ptrace_attach() won't work. Perhaps we will add another ->ptrace check later, we will see.

Link: http://lkml.kernel.org/r/20171103184206.GB21036@redhat.com Signed-off-by: Oleg Nesterov oleg@redhat.com Tested-by: Kyle Huey me@kylehuey.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- kernel/signal.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)

--- a/kernel/signal.c +++ b/kernel/signal.c @@ -94,13 +94,15 @@ static int sig_ignored(struct task_struc if (sigismember(&t->blocked, sig) || sigismember(&t->real_blocked, sig)) return 0;

- if (!sig_task_ignored(t, sig, force)) - return 0; - /* - * Tracers may want to know about even ignored signals. + * Tracers may want to know about even ignored signal unless it + * is SIGKILL which can't be reported anyway but can be ignored + * by SIGNAL_UNKILLABLE task. */ - return !t->ptrace; + if (t->ptrace && sig != SIGKILL) + return 0; + + return sig_task_ignored(t, sig, force); }

/*

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------------------

From: Oleg Nesterov oleg@redhat.com

commit 426915796ccaf9c2bd9bb06dc5702225957bc2e5 upstream.

complete_signal() checks SIGNAL_UNKILLABLE before it starts to destroy the thread group, today this is wrong in many ways.

If nothing else, fatal_signal_pending() should always imply that the whole thread group (except ->group_exit_task if it is not NULL) is killed, this check breaks the rule.

After the previous changes we can rely on sig_task_ignored(); sig_fatal(sig) && SIGNAL_UNKILLABLE can only be true if we actually want to kill this task and sig == SIGKILL OR it is traced and debugger can intercept the signal.

This should hopefully fix the problem reported by Dmitry. This test-case

static int init(void *arg) { for (;;) pause(); }

int main(void) { char stack[16 * 1024];

for (;;) { int pid = clone(init, stack + sizeof(stack)/2, CLONE_NEWPID | SIGCHLD, NULL); assert(pid > 0);

assert(ptrace(PTRACE_ATTACH, pid, 0, 0) == 0); assert(waitpid(-1, NULL, WSTOPPED) == pid);

assert(ptrace(PTRACE_DETACH, pid, 0, SIGSTOP) == 0); assert(syscall(__NR_tkill, pid, SIGKILL) == 0); assert(pid == wait(NULL)); } }

triggers the WARN_ON_ONCE(!(task->jobctl & JOBCTL_STOP_PENDING)) in task_participate_group_stop(). do_signal_stop()->signal_group_exit() checks SIGNAL_GROUP_EXIT and return false, but task_set_jobctl_pending() checks fatal_signal_pending() and does not set JOBCTL_STOP_PENDING.

And his should fix the minor security problem reported by Kyle, SECCOMP_RET_TRACE can miss fatal_signal_pending() the same way if the task is the root of a pid namespace.

Link: http://lkml.kernel.org/r/20171103184246.GD21036@redhat.com Signed-off-by: Oleg Nesterov oleg@redhat.com Reported-by: Dmitry Vyukov dvyukov@google.com Reported-by: Kyle Huey me@kylehuey.com Reviewed-by: Kees Cook keescook@chromium.org Tested-by: Kyle Huey me@kylehuey.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- kernel/signal.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/kernel/signal.c +++ b/kernel/signal.c @@ -931,9 +931,9 @@ static void complete_signal(int sig, str * then start taking the whole group down immediately. */ if (sig_fatal(p, sig) && - !(signal->flags & (SIGNAL_UNKILLABLE | SIGNAL_GROUP_EXIT)) && + !(signal->flags & SIGNAL_GROUP_EXIT) && !sigismember(&t->real_blocked, sig) && - (sig == SIGKILL || !t->ptrace)) { + (sig == SIGKILL || !p->ptrace)) { /* * This signal will be fatal to the whole group. */

4.14-stable review patch. If anyone has any objections, please let me know.

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From: Robin Murphy robin.murphy@arm.com

commit 563b5cbe334e9503ab2b234e279d500fc4f76018 upstream.

For PCI devices behind an aliasing PCIe-to-PCI/X bridge, the bridge alias to DevFn 0.0 on the subordinate bus may match the original RID of the device, resulting in the same SID being present in the device's fwspec twice. This causes trouble later in arm_smmu_write_strtab_ent() when we wind up visiting the STE a second time and find it already live.

Avoid the issue by giving arm_smmu_install_ste_for_dev() the cleverness to skip over duplicates. It seems mildly counterintuitive compared to preventing the duplicates from existing in the first place, but since the DT and ACPI probe paths build their fwspecs differently, this is actually the cleanest and most self-contained way to deal with it.

Fixes: 8f78515425da ("iommu/arm-smmu: Implement of_xlate() for SMMUv3") Reported-by: Tomasz Nowicki tomasz.nowicki@caviumnetworks.com Tested-by: Tomasz Nowicki Tomasz.Nowicki@cavium.com Tested-by: Jayachandran C. jnair@caviumnetworks.com Signed-off-by: Robin Murphy robin.murphy@arm.com Signed-off-by: Will Deacon will.deacon@arm.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- drivers/iommu/arm-smmu-v3.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)

--- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -1646,7 +1646,7 @@ static __le64 *arm_smmu_get_step_for_sid

static void arm_smmu_install_ste_for_dev(struct iommu_fwspec *fwspec) { - int i; + int i, j; struct arm_smmu_master_data *master = fwspec->iommu_priv; struct arm_smmu_device *smmu = master->smmu;

@@ -1654,6 +1654,13 @@ static void arm_smmu_install_ste_for_dev u32 sid = fwspec->ids[i]; __le64 *step = arm_smmu_get_step_for_sid(smmu, sid);

+ /* Bridged PCI devices may end up with duplicated IDs */ + for (j = 0; j < i; j++) + if (fwspec->ids[j] == sid) + break; + if (j < i) + continue; + arm_smmu_write_strtab_ent(smmu, sid, step, &master->ste); } }

4.14-stable review patch. If anyone has any objections, please let me know.

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From: John Sperbeck jsperbeck@google.com

commit ecb101aed86156ec7cd71e5dca668e09146e6994 upstream.

The recent refactoring of the powerpc page fault handler in commit c3350602e876 ("powerpc/mm: Make bad_area* helper functions") caused access to protected memory regions to indicate SEGV_MAPERR instead of the traditional SEGV_ACCERR in the si_code field of a user-space signal handler. This can confuse debug libraries that temporarily change the protection of memory regions, and expect to use SEGV_ACCERR as an indication to restore access to a region.

This commit restores the previous behavior. The following program exhibits the issue:

$ ./repro read || echo "FAILED" $ ./repro write || echo "FAILED" $ ./repro exec || echo "FAILED"

#include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <signal.h> #include <sys/mman.h> #include <assert.h>

static void segv_handler(int n, siginfo_t *info, void *arg) { _exit(info->si_code == SEGV_ACCERR ? 0 : 1); }

int main(int argc, char **argv) { void *p = NULL; struct sigaction act = { .sa_sigaction = segv_handler, .sa_flags = SA_SIGINFO, };

assert(argc == 2); p = mmap(NULL, getpagesize(), (strcmp(argv[1], "write") == 0) ? PROT_READ : 0, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); assert(p != MAP_FAILED);

assert(sigaction(SIGSEGV, &act, NULL) == 0); if (strcmp(argv[1], "read") == 0) printf("%c", *(unsigned char *)p); else if (strcmp(argv[1], "write") == 0) *(unsigned char *)p = 0; else if (strcmp(argv[1], "exec") == 0) ((void (*)(void))p)(); return 1; /* failed to generate SEGV */ }

Fixes: c3350602e876 ("powerpc/mm: Make bad_area* helper functions") Signed-off-by: John Sperbeck jsperbeck@google.com Acked-by: Benjamin Herrenschmidt benh@kernel.crashing.org [mpe: Add commit references in change log] Signed-off-by: Michael Ellerman mpe@ellerman.id.au Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- arch/powerpc/mm/fault.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)

--- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -145,6 +145,11 @@ static noinline int bad_area(struct pt_r return __bad_area(regs, address, SEGV_MAPERR); }

+static noinline int bad_access(struct pt_regs *regs, unsigned long address) +{ + return __bad_area(regs, address, SEGV_ACCERR); +} + static int do_sigbus(struct pt_regs *regs, unsigned long address, unsigned int fault) { @@ -490,7 +495,7 @@ retry:

good_area: if (unlikely(access_error(is_write, is_exec, vma))) - return bad_area(regs, address); + return bad_access(regs, address);

/* * If for any reason at all we couldn't handle the fault,

4.14-stable review patch. If anyone has any objections, please let me know.

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From: Tom Lendacky thomas.lendacky@amd.com

commit f4e9b7af0cd58dd039a0fb2cd67d57cea4889abf upstream.

The size for the Microcode Patch Block (MPB) for an AMD family 17h processor is 3200 bytes. Add a #define for fam17h so that it does not default to 2048 bytes and fail a microcode load/update.

Signed-off-by: Tom Lendacky thomas.lendacky@amd.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Reviewed-by: Borislav Petkov bp@alien8.de Link: https://lkml.kernel.org/r/20171130224640.15391.40247.stgit@tlendack-t1.amdof... Signed-off-by: Ingo Molnar mingo@kernel.org Cc: Alice Ferrazzi alicef@gentoo.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- arch/x86/kernel/cpu/microcode/amd.c | 4 ++++ 1 file changed, 4 insertions(+)

--- a/arch/x86/kernel/cpu/microcode/amd.c +++ b/arch/x86/kernel/cpu/microcode/amd.c @@ -470,6 +470,7 @@ static unsigned int verify_patch_size(u8 #define F14H_MPB_MAX_SIZE 1824 #define F15H_MPB_MAX_SIZE 4096 #define F16H_MPB_MAX_SIZE 3458 +#define F17H_MPB_MAX_SIZE 3200

switch (family) { case 0x14: @@ -481,6 +482,9 @@ static unsigned int verify_patch_size(u8 case 0x16: max_size = F16H_MPB_MAX_SIZE; break; + case 0x17: + max_size = F17H_MPB_MAX_SIZE; + break; default: max_size = F1XH_MPB_MAX_SIZE; break;

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From: Helge Deller deller@gmx.de

commit 310d82784fb4d60c80569f5ca9f53a7f3bf1d477 upstream.

Add qemu idle sleep support when running under qemu with SeaBIOS PDC firmware.

Like the power architecture we use the "or" assembler instructions, which translate to nops on real hardware, to indicate that qemu shall idle sleep.

Signed-off-by: Helge Deller deller@gmx.de Cc: Richard Henderson rth@twiddle.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- arch/parisc/kernel/process.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+)

--- a/arch/parisc/kernel/process.c +++ b/arch/parisc/kernel/process.c @@ -39,6 +39,7 @@ #include <linux/kernel.h> #include <linux/mm.h> #include <linux/fs.h> +#include <linux/cpu.h> #include <linux/module.h> #include <linux/personality.h> #include <linux/ptrace.h> @@ -184,6 +185,44 @@ int dump_task_fpu (struct task_struct *t }

/* + * Idle thread support + * + * Detect when running on QEMU with SeaBIOS PDC Firmware and let + * QEMU idle the host too. + */ + +int running_on_qemu __read_mostly; + +void __cpuidle arch_cpu_idle_dead(void) +{ + /* nop on real hardware, qemu will offline CPU. */ + asm volatile("or %%r31,%%r31,%%r31\n":::); +} + +void __cpuidle arch_cpu_idle(void) +{ + local_irq_enable(); + + /* nop on real hardware, qemu will idle sleep. */ + asm volatile("or %%r10,%%r10,%%r10\n":::); +} + +static int __init parisc_idle_init(void) +{ + const char *marker; + + /* check QEMU/SeaBIOS marker in PAGE0 */ + marker = (char *) &PAGE0->pad0; + running_on_qemu = (memcmp(marker, "SeaBIOS", 8) == 0); + + if (!running_on_qemu) + cpu_idle_poll_ctrl(1); + + return 0; +} +arch_initcall(parisc_idle_init); + +/* * Copy architecture-specific thread state */ int

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From: Christian Borntraeger borntraeger@de.ibm.com

commit c2cf265d860882b51a200e4a7553c17827f2b730 upstream.

We must not go beyond the pre-allocated buffer. This can happen when a new memory slot is added during migration.

Reported-by: David Hildenbrand david@redhat.com Signed-off-by: Christian Borntraeger borntraeger@de.ibm.com Fixes: 190df4a212a7 (KVM: s390: CMMA tracking, ESSA emulation, migration mode) Reviewed-by: Cornelia Huck cohuck@redhat.com Reviewed-by: David Hildenbrand david@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- arch/s390/kvm/priv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/s390/kvm/priv.c +++ b/arch/s390/kvm/priv.c @@ -1009,7 +1009,7 @@ static inline int do_essa(struct kvm_vcp cbrlo[entries] = gfn << PAGE_SHIFT; }

- if (orc) { + if (orc && gfn < ms->bitmap_size) { /* increment only if we are really flipping the bit to 1 */ if (!test_and_set_bit(gfn, ms->pgste_bitmap)) atomic64_inc(&ms->dirty_pages);