KVM: x86/mmu: Move root_hpa validity checks to top of page fault handler
Add a check on root_hpa at the beginning of the page fault handler to
consolidate several checks on root_hpa that are scattered throughout the
page fault code. This is a preparatory step towards eventually removing
such checks altogether, or at the very least WARNing if an invalid root
is encountered. Remove only the checks that can be easily audited to
confirm that root_hpa cannot be invalidated between their current
location and the new check in kvm_mmu_page_fault(), and aren't currently
protected by mmu_lock, i.e. keep the checks in __direct_map() and
FNAME(fetch) for the time being.
The root_hpa checks that are consolidate were all added by commit
which was a follow up to a bug fix for __direct_map(), commit
989c6b34f6a94 ("KVM: MMU: handle invalid root_hpa at __direct_map")
At the time, nested VMX had, in hindsight, crazy handling of nested
interrupts and would trigger a nested VM-Exit in ->interrupt_allowed(),
and thus unexpectedly reset the MMU in flows such as can_do_async_pf().
Now that the wonky nested VM-Exit behavior is gone, the root_hpa checks
are bogus and confusing, e.g. it's not at all obvious what they actually
protect against, and at first glance they appear to be broken since many
of them run without holding mmu_lock.
KVM: x86/mmu: Move calls to thp_adjust() down a level
Move the calls to thp_adjust() down a level from the page fault handlers
to the map/fetch helpers and remove the page count shuffling done in
thp_adjust().
Despite holding a reference to the underlying page while processing a
page fault, the page fault flows don't actually rely on holding a
reference to the page when thp_adjust() is called. At that point, the
fault handlers hold mmu_lock, which prevents mmu_notifier from completing
any invalidations, and have verified no invalidations from mmu_notifier
have occurred since the page reference was acquired (which is done prior
to taking mmu_lock).
The kvm_release_pfn_clean()/kvm_get_pfn() dance in thp_adjust() is a
quirk that is necessitated because thp_adjust() modifies the pfn that is
consumed by its caller. Because the page fault handlers call
kvm_release_pfn_clean() on said pfn, thp_adjust() needs to transfer the
reference to the correct pfn purely for correctness when the pfn is
released.
Calling thp_adjust() from __direct_map() and FNAME(fetch) means the pfn
adjustment doesn't change the pfn as seen by the page fault handlers,
i.e. the pfn released by the page fault handlers is the same pfn that
was returned by gfn_to_pfn().
KVM: x86/mmu: Consolidate tdp_page_fault() and nonpaging_page_fault()
Consolidate the direct MMU page fault handlers into a common helper,
direct_page_fault(). Except for unique max level conditions, the tdp
and nonpaging fault handlers are functionally identical.
KVM: x86/mmu: Rename lpage_disallowed to account_disallowed_nx_lpage
Rename __direct_map()'s param that controls whether or not a disallowed
NX large page should be accounted to match what it actually does. The
nonpaging_page_fault() case unconditionally passes %false for the param
even though it locally sets lpage_disallowed.
KVM: x86/mmu: Persist gfn_lpage_is_disallowed() to max_level
Persist the max page level calculated via gfn_lpage_is_disallowed() to
the max level "returned" by mapping_level() so that its naturally taken
into account by the max level check that conditions calling
transparent_hugepage_adjust().
Drop the gfn_lpage_is_disallowed() check in thp_adjust() as it's now
handled by mapping_level() and its callers.
Add a comment to document the behavior of host_mapping_level() and its
interaction with max level and transparent huge pages.
Note, transferring the gfn_lpage_is_disallowed() from thp_adjust() to
mapping_level() superficially affects how changes to a memslot's
disallow_lpage count will be handled due to thp_adjust() being run while
holding mmu_lock.
In the more common case where a different vCPU increments the count via
account_shadowed(), gfn_lpage_is_disallowed() is rechecked by set_spte()
to ensure a writable large page isn't created.
In the less common case where the count is decremented to zero due to
all shadow pages in the memslot being zapped, THP behavior now matches
hugetlbfs behavior in the sense that a small page will be created when a
large page could be used if the count reaches zero in the miniscule
window between mapping_level() and acquiring mmu_lock.
Lastly, the new THP behavior also follows hugetlbfs behavior in the
absurdly unlikely scenario of a memslot being moved such that the
memslot's compatibility with respect to large pages changes, but without
changing the validity of the gpf->pfn walk. I.e. if a memslot is moved
between mapping_level() and snapshotting mmu_seq, it's theoretically
possible to consume a stale disallow_lpage count. But, since KVM zaps
all shadow pages when moving a memslot and forces all vCPUs to reload a
new MMU, the inserted spte will always be thrown away prior to
completing the memslot move, i.e. whether or not the spte accurately
reflects disallow_lpage is irrelevant.
KVM: x86/mmu: Incorporate guest's page level into max level for shadow MMU
Restrict the max level for a shadow page based on the guest's level
instead of capping the level after the fact for host-mapped huge pages,
e.g. hugetlbfs pages. Explicitly capping the max level using the guest
mapping level also eliminates FNAME(page_fault)'s subtle dependency on
THP only supporting 2mb pages.
KVM: x86/mmu: Refactor handling of forced 4k pages in page faults
Refactor the page fault handlers and mapping_level() to track the max
allowed page level instead of only tracking if a 4k page is mandatory
due to one restriction or another. This paves the way for cleanly
consolidating tdp_page_fault() and nonpaging_page_fault(), and for
eliminating a redundant check on mmu_gfn_lpage_is_disallowed().
KVM: x86/mmu: Refactor the per-slot level calculation in mapping_level()
Invert the loop which adjusts the allowed page level based on what's
compatible with the associated memslot to use a largest-to-smallest
page size walk. This paves the way for passing around a "max level"
variable instead of having redundant checks and/or multiple booleans.
KVM: x86/mmu: Refactor handling of cache consistency with TDP
Pre-calculate the max level for a TDP page with respect to MTRR cache
consistency in preparation of replacing force_pt_level with max_level,
and eventually combining the bulk of nonpaging_page_fault() and
tdp_page_fault() into a common helper.
Move nonpaging_page_fault() below try_async_pf() to eliminate the
forward declaration of try_async_pf() and to prepare for combining the
bulk of nonpaging_page_fault() and tdp_page_fault() into a common
helper.
KVM: x86/mmu: Fold nonpaging_map() into nonpaging_page_fault()
Fold nonpaging_map() into its sole caller, nonpaging_page_fault(), in
preparation for combining the bulk of nonpaging_page_fault() and
tdp_page_fault() into a common helper.
KVM: x86: Use gpa_t for cr2/gpa to fix TDP support on 32-bit KVM
Convert a plethora of parameters and variables in the MMU and page fault
flows from type gva_t to gpa_t to properly handle TDP on 32-bit KVM.
Thanks to PSE and PAE paging, 32-bit kernels can access 64-bit physical
addresses. When TDP is enabled, the fault address is a guest physical
address and thus can be a 64-bit value, even when both KVM and its guest
are using 32-bit virtual addressing, e.g. VMX's VMCS.GUEST_PHYSICAL is a
64-bit field, not a natural width field.
Using a gva_t for the fault address means KVM will incorrectly drop the
upper 32-bits of the GPA. Ditto for gva_to_gpa() when it is used to
translate L2 GPAs to L1 GPAs.
Opportunistically rename variables and parameters to better reflect the
dual address modes, e.g. use "cr2_or_gpa" for fault addresses and plain
"addr" instead of "vaddr" when the address may be either a GVA or an L2
GPA. Similarly, use "gpa" in the nonpaging_page_fault() flows to avoid
a confusing "gpa_t gva" declaration; this also sets the stage for a
future patch to combing nonpaging_page_fault() and tdp_page_fault() with
minimal churn.
Sprinkle in a few comments to document flows where an address is known
to be a GVA and thus can be safely truncated to a 32-bit value. Add
WARNs in kvm_handle_page_fault() and FNAME(gva_to_gpa_nested)() to help
document such cases and detect bugs.
KVM: x86: Add a WARN on TIF_NEED_FPU_LOAD in kvm_load_guest_fpu()
WARN once in kvm_load_guest_fpu() if TIF_NEED_FPU_LOAD is observed, as
that would mean that KVM is corrupting userspace's FPU by saving
unknown register state into arch.user_fpu. Add a comment to explain
why KVM WARNs on TIF_NEED_FPU_LOAD instead of implementing logic
similar to fpu__copy().
KVM: x86: Fix potential put_fpu() w/o load_fpu() on MPX platform
Unlike most state managed by XSAVE, MPX is initialized to zero on INIT.
Because INITs are usually recognized in the context of a VCPU_RUN call,
kvm_vcpu_reset() puts the guest's FPU so that the FPU state is resident
in memory, zeros the MPX state, and reloads FPU state to hardware. But,
in the unlikely event that an INIT is recognized during
kvm_arch_vcpu_ioctl_get_mpstate() via kvm_apic_accept_events(),
kvm_vcpu_reset() will call kvm_put_guest_fpu() without a preceding
kvm_load_guest_fpu() and corrupt the guest's FPU state (and possibly
userspace's FPU state as well).
Given that MPX is being removed from the kernel[*], fix the bug with the
simple-but-ugly approach of loading the guest's FPU during
KVM_GET_MP_STATE.
[*] See commit f240652b6032b ("x86/mpx: Remove MPX APIs").
Fixes: f775b13eedee2 ("x86,kvm: move qemu/guest FPU switching out to vcpu_run") Cc: [email protected] Signed-off-by: Sean Christopherson <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
Jim Mattson [Fri, 6 Dec 2019 23:46:37 +0000 (15:46 -0800)]
kvm: nVMX: Aesthetic cleanup of handle_vmread and handle_vmwrite
Apply reverse fir tree declaration order, shorten some variable names
to avoid line wrap, reformat a block comment, delete an extra blank
line, and use BIT(10) instead of (1u << 10).
Jim Mattson [Fri, 6 Dec 2019 23:46:36 +0000 (15:46 -0800)]
kvm: nVMX: VMWRITE checks unsupported field before read-only field
According to the SDM, VMWRITE checks to see if the secondary source
operand corresponds to an unsupported VMCS field before it checks to
see if the secondary source operand corresponds to a VM-exit
information field and the processor does not support writing to
VM-exit information fields.
Jim Mattson [Fri, 6 Dec 2019 23:46:35 +0000 (15:46 -0800)]
kvm: nVMX: VMWRITE checks VMCS-link pointer before VMCS field
According to the SDM, a VMWRITE in VMX non-root operation with an
invalid VMCS-link pointer results in VMfailInvalid before the validity
of the VMCS field in the secondary source operand is checked.
For consistency, modify both handle_vmwrite and handle_vmread, even
though there was no problem with the latter.
Peter Xu [Wed, 4 Dec 2019 19:07:20 +0000 (20:07 +0100)]
KVM: X86: Fix callers of kvm_apic_match_dest() to use correct macros
Callers of kvm_apic_match_dest() should always pass in APIC_DEST_*
macros for either dest_mode and short_hand parameters. Fix up all the
callers of kvm_apic_match_dest() that are not following the rule.
Since at it, rename the parameter from short_hand to shorthand in
kvm_apic_match_dest(), as suggested by Vitaly.
Peter Xu [Wed, 4 Dec 2019 19:07:19 +0000 (20:07 +0100)]
KVM: X86: Drop KVM_APIC_SHORT_MASK and KVM_APIC_DEST_MASK
We have both APIC_SHORT_MASK and KVM_APIC_SHORT_MASK defined for the
shorthand mask. Similarly, we have both APIC_DEST_MASK and
KVM_APIC_DEST_MASK defined for the destination mode mask.
Drop the KVM_APIC_* macros and replace the only user of them to use
the APIC_DEST_* macros instead. At the meantime, move APIC_SHORT_MASK
and APIC_DEST_MASK from lapic.c to lapic.h.
Peter Xu [Wed, 4 Dec 2019 19:07:18 +0000 (20:07 +0100)]
KVM: X86: Use APIC_DEST_* macros properly in kvm_lapic_irq.dest_mode
We were using either APIC_DEST_PHYSICAL|APIC_DEST_LOGICAL or 0|1 to
fill in kvm_lapic_irq.dest_mode. It's fine only because in most cases
when we check against dest_mode it's against APIC_DEST_PHYSICAL (which
equals to 0). However, that's not consistent. We'll have problem
when we want to start checking against APIC_DEST_LOGICAL, which does
not equals to 1.
This patch firstly introduces kvm_lapic_irq_dest_mode() helper to take
any boolean of destination mode and return the APIC_DEST_* macro.
Then, it replaces the 0|1 settings of irq.dest_mode with the helper.
Miaohe Lin [Thu, 5 Dec 2019 03:40:16 +0000 (11:40 +0800)]
KVM: explicitly set rmap_head->val to 0 in pte_list_desc_remove_entry()
When we reach here, we have desc->sptes[j] = NULL with j = 0.
So we can replace desc->sptes[0] with 0 to make it more clear. Signed-off-by: Miaohe Lin <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
Miaohe Lin [Thu, 5 Dec 2019 03:05:05 +0000 (11:05 +0800)]
KVM: get rid of var page in kvm_set_pfn_dirty()
We can get rid of unnecessary var page in
kvm_set_pfn_dirty() , thus make code style
similar with kvm_set_pfn_accessed(). Signed-off-by: Miaohe Lin <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
Paolo Bonzini [Wed, 4 Dec 2019 14:50:27 +0000 (15:50 +0100)]
KVM: x86: use CPUID to locate host page table reserved bits
The comment in kvm_get_shadow_phys_bits refers to MKTME, but the same is actually
true of SME and SEV. Just use CPUID[0x8000_0008].EAX[7:0] unconditionally if
available, it is simplest and works even if memory is not encrypted.
Linus Torvalds [Sun, 5 Jan 2020 19:15:31 +0000 (11:15 -0800)]
Merge tag 'riscv/for-v5.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V fixes from Paul Walmsley:
"Several fixes for RISC-V:
- Fix function graph trace support
- Prefix the CSR IRQ_* macro names with "RV_", to avoid collisions
with macros elsewhere in the Linux kernel tree named "IRQ_TIMER"
- Use __pa_symbol() when computing the physical address of a kernel
symbol, rather than __pa()
- Mark the RISC-V port as supporting GCOV
One DT addition:
- Describe the L2 cache controller in the FU540 DT file
One documentation update:
- Add patch acceptance guideline documentation"
* tag 'riscv/for-v5.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
Documentation: riscv: add patch acceptance guidelines
riscv: prefix IRQ_ macro names with an RV_ namespace
clocksource: riscv: add notrace to riscv_sched_clock
riscv: ftrace: correct the condition logic in function graph tracer
riscv: dts: Add DT support for SiFive L2 cache controller
riscv: gcov: enable gcov for RISC-V
riscv: mm: use __pa_symbol for kernel symbols
Formalize, in kernel documentation, the patch acceptance policy for
arch/riscv. In summary, it states that as maintainers, we plan to
only accept patches for new modules or extensions that have been
frozen or ratified by the RISC-V Foundation.
We've been following these guidelines for the past few months. In the
meantime, we've received quite a bit of feedback that it would be
helpful to have these guidelines formally documented.
Based on a suggestion from Matthew Wilcox, we also add a link to this
file to Documentation/process/index.rst, to make this document easier
to find. The format of this document has also been changed to align
to the format outlined in the maintainer entry profiles, in accordance
with comments from Jon Corbet and Dan Williams.
Paul Walmsley [Fri, 20 Dec 2019 11:09:49 +0000 (03:09 -0800)]
riscv: prefix IRQ_ macro names with an RV_ namespace
"IRQ_TIMER", used in the arch/riscv CSR header file, is a sufficiently
generic macro name that it's used by several source files across the
Linux code base. Some of these other files ultimately include the
arch/riscv CSR include file, causing collisions. Fix by prefixing the
RISC-V csr.h IRQ_ macro names with an RV_ prefix.
Fixes: a4c3733d32a72 ("riscv: abstract out CSR names for supervisor vs machine mode") Reported-by: Olof Johansson <[email protected]> Acked-by: Olof Johansson <[email protected]> Signed-off-by: Paul Walmsley <[email protected]>
Zong Li [Mon, 23 Dec 2019 08:46:14 +0000 (16:46 +0800)]
clocksource: riscv: add notrace to riscv_sched_clock
When enabling ftrace graph tracer, it gets the tracing clock in
ftrace_push_return_trace(). Eventually, it invokes riscv_sched_clock()
to get the clock value. If riscv_sched_clock() isn't marked with
'notrace', it will call ftrace_push_return_trace() and cause infinite
loop.
Linus Torvalds [Sun, 5 Jan 2020 03:38:51 +0000 (19:38 -0800)]
Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
"17 fixes"
* emailed patches from Andrew Morton <[email protected]>:
hexagon: define ioremap_uc
ocfs2: fix the crash due to call ocfs2_get_dlm_debug once less
ocfs2: call journal flush to mark journal as empty after journal recovery when mount
mm/hugetlb: defer freeing of huge pages if in non-task context
mm/gup: fix memory leak in __gup_benchmark_ioctl
mm/oom: fix pgtables units mismatch in Killed process message
fs/posix_acl.c: fix kernel-doc warnings
hexagon: work around compiler crash
hexagon: parenthesize registers in asm predicates
fs/namespace.c: make to_mnt_ns() static
fs/nsfs.c: include headers for missing declarations
fs/direct-io.c: include fs/internal.h for missing prototype
mm: move_pages: return valid node id in status if the page is already on the target node
memcg: account security cred as well to kmemcg
kcov: fix struct layout for kcov_remote_arg
mm/zsmalloc.c: fix the migrated zspage statistics.
mm/memory_hotplug: shrink zones when offlining memory
Linus Torvalds [Sun, 5 Jan 2020 03:28:30 +0000 (19:28 -0800)]
Merge tag 'apparmor-pr-2020-01-04' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor
Pull apparmor fixes from John Johansen:
- performance regression: only get a label reference if the fast path
check fails
- fix aa_xattrs_match() may sleep while holding a RCU lock
- fix bind mounts aborting with -ENOMEM
* tag 'apparmor-pr-2020-01-04' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor:
apparmor: fix aa_xattrs_match() may sleep while holding a RCU lock
apparmor: only get a label reference if the fast path check fails
apparmor: fix bind mounts aborting with -ENOMEM
John Johansen [Thu, 2 Jan 2020 13:31:22 +0000 (05:31 -0800)]
apparmor: fix aa_xattrs_match() may sleep while holding a RCU lock
aa_xattrs_match() is unfortunately calling vfs_getxattr_alloc() from a
context protected by an rcu_read_lock. This can not be done as
vfs_getxattr_alloc() may sleep regardles of the gfp_t value being
passed to it.
Fix this by breaking the rcu_read_lock on the policy search when the
xattr match feature is requested and restarting the search if a policy
changes occur.
Fixes: 8e51f9087f40 ("apparmor: Add support for attaching profiles via xattr, presence and value") Reported-by: Jia-Ju Bai <[email protected]> Reported-by: Al Viro <[email protected]> Signed-off-by: John Johansen <[email protected]>
Linus Torvalds [Sat, 4 Jan 2020 22:16:57 +0000 (14:16 -0800)]
Merge tag 'mips_fixes_5.5_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux
Pull MIPS fixes from Paul Burton:
"A collection of MIPS fixes:
- Fill the struct cacheinfo shared_cpu_map field with sensible
values, notably avoiding issues with perf which was unhappy in the
absence of these values.
- A boot fix for Loongson 2E & 2F machines which was fallout from
some refactoring performed this cycle.
- A Kconfig dependency fix for the Loongson CPU HWMon driver.
- A couple of VDSO fixes, ensuring gettimeofday() behaves
appropriately for kernel configurations that don't include support
for a clocksource the VDSO can use & fixing the calling convention
for the n32 & n64 VDSOs which would previously clobber the $gp/$28
register.
- A build fix for vmlinuz compressed images which were
inappropriately building with -fsanitize-coverage despite not being
part of the kernel proper, then failing to link due to the missing
__sanitizer_cov_trace_pc() function.
- A couple of eBPF JIT fixes, including disabling it for MIPS32 due
to a large number of issues with the code generated there &
reflecting ISA dependencies in Kconfig to enforce that systems
which don't support the JIT must include the interpreter"
* tag 'mips_fixes_5.5_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
MIPS: Avoid VDSO ABI breakage due to global register variable
MIPS: BPF: eBPF JIT: check for MIPS ISA compliance in Kconfig
MIPS: BPF: Disable MIPS32 eBPF JIT
MIPS: Prevent link failure with kcov instrumentation
MIPS: Kconfig: Use correct form for 'depends on'
mips: Fix gettimeofday() in the vdso library
MIPS: Fix boot on Fuloong2 systems
mips: cacheinfo: report shared CPU map
Gang He [Sat, 4 Jan 2020 21:00:22 +0000 (13:00 -0800)]
ocfs2: fix the crash due to call ocfs2_get_dlm_debug once less
Because ocfs2_get_dlm_debug() function is called once less here, ocfs2
file system will trigger the system crash, usually after ocfs2 file
system is unmounted.
This system crash is caused by a generic memory corruption, these crash
backtraces are not always the same, for exapmle,
Kai Li [Sat, 4 Jan 2020 21:00:18 +0000 (13:00 -0800)]
ocfs2: call journal flush to mark journal as empty after journal recovery when mount
If journal is dirty when mount, it will be replayed but jbd2 sb log tail
cannot be updated to mark a new start because journal->j_flag has
already been set with JBD2_ABORT first in journal_init_common.
When a new transaction is committed, it will be recored in block 1
first(journal->j_tail is set to 1 in journal_reset). If emergency
restart happens again before journal super block is updated
unfortunately, the new recorded trans will not be replayed in the next
mount.
The following steps describe this procedure in detail.
1. mount and touch some files
2. these transactions are committed to journal area but not checkpointed
3. emergency restart
4. mount again and its journals are replayed
5. journal super block's first s_start is 1, but its s_seq is not updated
6. touch a new file and its trans is committed but not checkpointed
7. emergency restart again
8. mount and journal is dirty, but trans committed in 6 will not be
replayed.
This exception happens easily when this lun is used by only one node.
If it is used by multi-nodes, other node will replay its journal and its
journal super block will be updated after recovery like what this patch
does.
ocfs2_recover_node->ocfs2_replay_journal.
The following jbd2 journal can be generated by touching a new file after
journal is replayed, and seq 15 is the first valid commit, but first seq
is 13 in journal super block.
The following is journal recovery log when recovering the upper jbd2
journal when mount again.
syslog:
ocfs2: File system on device (252,1) was not unmounted cleanly, recovering it.
fs/jbd2/recovery.c:(do_one_pass, 449): Starting recovery pass 0
fs/jbd2/recovery.c:(do_one_pass, 449): Starting recovery pass 1
fs/jbd2/recovery.c:(do_one_pass, 449): Starting recovery pass 2
fs/jbd2/recovery.c:(jbd2_journal_recover, 278): JBD2: recovery, exit status 0, recovered transactions 13 to 13
Due to first commit seq 13 recorded in journal super is not consistent
with the value recorded in block 1(seq is 14), journal recovery will be
terminated before seq 15 even though it is an unbroken commit, inode 8257802 is a new file and it will be lost.
Both the hugetbl_lock and the subpool lock can be acquired in
free_huge_page(). One way to solve the problem is to make both locks
irq-safe. However, Mike Kravetz had learned that the hugetlb_lock is
held for a linear scan of ALL hugetlb pages during a cgroup reparentling
operation. So it is just too long to have irq disabled unless we can
break hugetbl_lock down into finer-grained locks with shorter lock hold
times.
Another alternative is to defer the freeing to a workqueue job. This
patch implements the deferred freeing by adding a free_hpage_workfn()
work function to do the actual freeing. The free_huge_page() call in a
non-task context saves the page to be freed in the hpage_freelist linked
list in a lockless manner using the llist APIs.
The generic workqueue is used to process the work, but a dedicated
workqueue can be used instead if it is desirable to have the huge page
freed ASAP.
Thanks to Kirill Tkhai <[email protected]> for suggesting the use of
llist APIs which simplfy the code.
Navid Emamdoost [Sat, 4 Jan 2020 21:00:12 +0000 (13:00 -0800)]
mm/gup: fix memory leak in __gup_benchmark_ioctl
In the implementation of __gup_benchmark_ioctl() the allocated pages
should be released before returning in case of an invalid cmd. Release
pages via kvfree().
Ilya Dryomov [Sat, 4 Jan 2020 21:00:09 +0000 (13:00 -0800)]
mm/oom: fix pgtables units mismatch in Killed process message
pr_err() expects kB, but mm_pgtables_bytes() returns the number of bytes.
As everything else is printed in kB, I chose to fix the value rather than
the string.
Before:
[ pid ] uid tgid total_vm rss pgtables_bytes swapents oom_score_adj name
...
[ 1878] 1000 1878 217253 151144 1269760 0 0 python
...
Out of memory: Killed process 1878 (python) total-vm:869012kB, anon-rss:604572kB, file-rss:4kB, shmem-rss:0kB, UID:1000 pgtables:1269760kB oom_score_adj:0
After:
[ pid ] uid tgid total_vm rss pgtables_bytes swapents oom_score_adj name
...
[ 1436] 1000 1436 217253 151890 1294336 0 0 python
...
Out of memory: Killed process 1436 (python) total-vm:869012kB, anon-rss:607516kB, file-rss:44kB, shmem-rss:0kB, UID:1000 pgtables:1264kB oom_score_adj:0
Randy Dunlap [Sat, 4 Jan 2020 21:00:05 +0000 (13:00 -0800)]
fs/posix_acl.c: fix kernel-doc warnings
Fix kernel-doc warnings in fs/posix_acl.c.
Also fix one typo (setgit -> setgid).
fs/posix_acl.c:647: warning: Function parameter or member 'inode' not described in 'posix_acl_update_mode'
fs/posix_acl.c:647: warning: Function parameter or member 'mode_p' not described in 'posix_acl_update_mode'
fs/posix_acl.c:647: warning: Function parameter or member 'acl' not described in 'posix_acl_update_mode'
Eric Biggers [Sat, 4 Jan 2020 20:59:52 +0000 (12:59 -0800)]
fs/nsfs.c: include headers for missing declarations
Include linux/proc_fs.h and fs/internal.h to address the following
'sparse' warnings:
fs/nsfs.c:41:32: warning: symbol 'ns_dentry_operations' was not declared. Should it be static?
fs/nsfs.c:145:5: warning: symbol 'open_related_ns' was not declared. Should it be static?
This is because the status is not set if the page is already on the
target node, but move_pages() should return valid status as long as it
succeeds. The valid status may be errno or node id.
We can't simply initialize status array to zero since the pages may be
not on node 0. Fix it by updating status with node id which the page is
already on.
Shakeel Butt [Sat, 4 Jan 2020 20:59:43 +0000 (12:59 -0800)]
memcg: account security cred as well to kmemcg
The cred_jar kmem_cache is already memcg accounted in the current kernel
but cred->security is not. Account cred->security to kmemcg.
Recently we saw high root slab usage on our production and on further
inspection, we found a buggy application leaking processes. Though that
buggy application was contained within its memcg but we observe much
more system memory overhead, couple of GiBs, during that period. This
overhead can adversely impact the isolation on the system.
One source of high overhead we found was cred->security objects, which
have a lifetime of at least the life of the process which allocated
them.
Make the layout of kcov_remote_arg the same for 32-bit and 64-bit code.
This makes it more convenient to write userspace apps that can be
compiled into 32-bit or 64-bit binaries and still work with the same
64-bit kernel.
Also use proper __u32 types in uapi headers instead of unsigned ints.
Chanho Min [Sat, 4 Jan 2020 20:59:36 +0000 (12:59 -0800)]
mm/zsmalloc.c: fix the migrated zspage statistics.
When zspage is migrated to the other zone, the zone page state should be
updated as well, otherwise the NR_ZSPAGE for each zone shows wrong
counts including proc/zoneinfo in practice.
mm/memory_hotplug: shrink zones when offlining memory
We currently try to shrink a single zone when removing memory. We use
the zone of the first page of the memory we are removing. If that
memmap was never initialized (e.g., memory was never onlined), we will
read garbage and can trigger kernel BUGs (due to a stale pointer):
Instead, shrink the zones when offlining memory or when onlining failed.
Introduce and use remove_pfn_range_from_zone(() for that. We now
properly shrink the zones, even if we have DIMMs whereby
- Some memory blocks fall into no zone (never onlined)
- Some memory blocks fall into multiple zones (offlined+re-onlined)
- Multiple memory blocks that fall into different zones
Drop the zone parameter (with a potential dubious value) from
__remove_pages() and __remove_section().
Linus Torvalds [Sat, 4 Jan 2020 18:49:15 +0000 (10:49 -0800)]
Merge tag 'dmaengine-fix-5.5-rc5' of git://git.infradead.org/users/vkoul/slave-dma
Pull dmaengine fixes from Vinod Koul:
"A bunch of fixes for:
- uninitialized dma_slave_caps access
- virt-dma use after free in vchan_complete()
- driver fixes for ioat, k3dma and jz4780"
* tag 'dmaengine-fix-5.5-rc5' of git://git.infradead.org/users/vkoul/slave-dma:
ioat: ioat_alloc_ring() failure handling.
dmaengine: virt-dma: Fix access after free in vchan_complete()
dmaengine: k3dma: Avoid null pointer traversal
dmaengine: dma-jz4780: Also break descriptor chains on JZ4725B
dmaengine: Fix access to uninitialized dma_slave_caps
Linus Torvalds [Sat, 4 Jan 2020 18:41:08 +0000 (10:41 -0800)]
Merge tag 'media/v5.5-3' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media fixes from Mauro Carvalho Chehab:
- some fixes at CEC core to comply with HDMI 2.0 specs and fix some
border cases
- a fix at the transmission logic of the pulse8-cec driver
- one alignment fix on a data struct at ipu3 when built with 32 bits
* tag 'media/v5.5-3' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
media: intel-ipu3: Align struct ipu3_uapi_awb_fr_config_s to 32 bytes
media: pulse8-cec: fix lost cec_transmit_attempt_done() call
media: cec: check 'transmit_in_progress', not 'transmitting'
media: cec: avoid decrementing transmit_queue_sz if it is 0
media: cec: CEC 2.0-only bcast messages were ignored
Linus Torvalds [Fri, 3 Jan 2020 20:20:21 +0000 (12:20 -0800)]
Merge tag 'for-5.5-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"A few fixes for btrfs:
- blkcg accounting problem with compression that could stall writes
- setting up blkcg bio for compression crashes due to NULL bdev
pointer
- fix possible infinite loop in writeback for nocow files (here
possible means almost impossible, 13 things that need to happen to
trigger it)"
* tag 'for-5.5-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
Btrfs: fix infinite loop during nocow writeback due to race
btrfs: fix compressed write bio blkcg attribution
btrfs: punt all bios created in btrfs_submit_compressed_write()
This makes it hard to extract a useable coredump for global init
from a kernel crashdump because by the time we panic exit_mm() will
have already released global init's mm. We now panic slightly
earlier. This has been a problem in certain environments such as
Android.
- Fix a race in assigning and reading taskstats for thread-groups
with more than one thread.
This patch has been waiting for quite a while since people
disagreed on what the correct fix was at first"
* tag 'for-linus-2020-01-03' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
exit: panic before exit_mm() on global init exit
taskstats: fix data-race
Linus Torvalds [Fri, 3 Jan 2020 19:13:50 +0000 (11:13 -0800)]
Merge tag 'powerpc-5.5-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
"Two more powerpc fixes for 5.5:
- One commit to fix a build error when CONFIG_JUMP_LABEL=n,
introduced by our recent fix to is_shared_processor().
- A commit marking some SLB related functions as notrace, as tracing
them triggers warnings.
Thanks to Jason A Donenfeld"
* tag 'powerpc-5.5-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/spinlocks: Include correct header for static key
powerpc/mm: Mark get_slice_psize() & slice_addr_is_low() as notrace
Linus Torvalds [Fri, 3 Jan 2020 19:10:31 +0000 (11:10 -0800)]
Merge tag 'sound-5.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"Nothing to worry at this stage but all nice small changes:
- A regression fix for AMD GPU detection in HD-audio
- A long-standing sleep-in-atomic fix for an ice1724 device
- Usual suspects, the device-specific quirks for HD- and USB-audio"
* tag 'sound-5.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: hda/realtek - Enable the bass speaker of ASUS UX431FLC
ALSA: ice1724: Fix sleep-in-atomic in Infrasonic Quartet support code
ALSA: hda/realtek - Add Bass Speaker and fixed dac for bass speaker
ALSA: hda - Apply sync-write workaround to old Intel platforms, too
ALSA: hda/hdmi - fix atpx_present when CLASS is not VGA
ALSA: usb-audio: fix set_format altsetting sanity check
ALSA: hda/realtek - Add headset Mic no shutup for ALC283
ALSA: usb-audio: set the interface format after resume on Dell WD19
The problem is the check introduced to for_each_hstate() loop that
should skip default_hstate_idx. Since it doesn't update 'i' counter,
all subsequent huge page sizes are skipped as well.
Fixes: 8fc312b32b25 ("mm/hugetlbfs: fix error handling when setting up mounts") Signed-off-by: Jan Stancek <[email protected]> Reviewed-by: Mike Kravetz <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
Ard Biesheuvel [Mon, 30 Dec 2019 14:07:47 +0000 (15:07 +0100)]
kbuild/deb-pkg: annotate libelf-dev dependency as :native
Cross compiling the x86 kernel on a non-x86 build machine produces
the following error when CONFIG_UNWINDER_ORC is enabled, regardless
of whether libelf-dev is installed or not.
dpkg-checkbuilddeps: error: Unmet build dependencies: libelf-dev
dpkg-buildpackage: warning: build dependencies/conflicts unsatisfied; aborting
dpkg-buildpackage: warning: (Use -d flag to override.)
Since this is a build time dependency for a build tool, we need to
depend on the native version of libelf-dev so add the appropriate
annotation.
Prior to commit 858805b336be ("kbuild: add $(BASH) to run scripts with
bash-extension"), this shell script was almost always run by bash since
bash is usually installed on the system by default.
Now, this script is run by sh, which might be a symlink to dash. On such
distributions, the following code emits an error:
local dev=`LC_ALL=C ls -l "${location}"`
You can reproduce the build error, for example by setting
CONFIG_INITRAMFS_SOURCE="/dev".
GEN usr/initramfs_data.cpio.gz
./usr/gen_initramfs_list.sh: 131: local: 1: bad variable name
make[1]: *** [usr/Makefile:61: usr/initramfs_data.cpio.gz] Error 2
This is because `LC_ALL=C ls -l "${location}"` contains spaces.
Surrounding it with double-quotes fixes the error.
Fixes: 858805b336be ("kbuild: add $(BASH) to run scripts with bash-extension") Reported-by: Jory A. Pratt <[email protected]> Signed-off-by: Masahiro Yamada <[email protected]>
Sakari Ailus [Wed, 6 Nov 2019 11:57:07 +0000 (12:57 +0100)]
media: intel-ipu3: Align struct ipu3_uapi_awb_fr_config_s to 32 bytes
A struct that needs to be aligned to 32 bytes has a size of 28. Increase
the size to 32.
This makes elements of arrays of this struct aligned to 32 as well, and
other structs where members are aligned to 32 mixing
ipu3_uapi_awb_fr_config_s as well as other types.
Fixes: commit dca5ef2aa1e6 ("media: staging/intel-ipu3: remove the unnecessary compiler flags") Signed-off-by: Sakari Ailus <[email protected]> Tested-by: Bingbu Cao <[email protected]> Signed-off-by: Mauro Carvalho Chehab <[email protected]>
Yunfeng Ye [Tue, 17 Dec 2019 12:22:57 +0000 (20:22 +0800)]
agp: remove unused variable arqsz in agp_3_5_enable()
This patch fix the following warning:
drivers/char/agp/isoch.c: In function ‘agp_3_5_enable’:
drivers/char/agp/isoch.c:322:13: warning: variable ‘arqsz’ set but not
used [-Wunused-but-set-variable]
u32 isoch, arqsz;
^~~~~
Yunfeng Ye [Tue, 17 Dec 2019 12:21:37 +0000 (20:21 +0800)]
agp: remove unused variable mcapndx
This patch fix the following warning:
drivers/char/agp/isoch.c: In function ‘agp_3_5_isochronous_node_enable’:
drivers/char/agp/isoch.c:87:5: warning: variable ‘mcapndx’ set but not
used [-Wunused-but-set-variable]
u8 mcapndx;
^~~~~~~
Linus Torvalds [Fri, 3 Jan 2020 00:46:30 +0000 (16:46 -0800)]
Merge tag 'gcc-plugins-v5.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull gcc-plugins fix from Kees Cook:
"Build flexibility fix: allow builds to disable plugins even when
plugins available (Arnd Bergmann)"
* tag 'gcc-plugins-v5.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
gcc-plugins: make it possible to disable CONFIG_GCC_PLUGINS again
Linus Torvalds [Fri, 3 Jan 2020 00:42:10 +0000 (16:42 -0800)]
Merge tag 'seccomp-v5.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull seccomp fixes from Kees Cook:
"Fixes for seccomp_notify_ioctl uapi sanity from Sargun Dhillon.
The bulk of this is fixing the surrounding samples and selftests so
that seccomp can correctly validate the seccomp_notify_ioctl buffer as
being initially zeroed.
Summary:
- Fix samples and selftests to zero passed-in buffer
- Enforce zeroed buffer checking
- Verify buffer sanity check in selftest"
* tag 'seccomp-v5.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
selftests/seccomp: Catch garbage on SECCOMP_IOCTL_NOTIF_RECV
seccomp: Check that seccomp_notif is zeroed out by the user
selftests/seccomp: Zero out seccomp_notif
samples/seccomp: Zero out members based on seccomp_notif_sizes
Paul Burton [Thu, 2 Jan 2020 04:50:38 +0000 (20:50 -0800)]
MIPS: Avoid VDSO ABI breakage due to global register variable
Declaring __current_thread_info as a global register variable has the
effect of preventing GCC from saving & restoring its value in cases
where the ABI would typically do so.
To quote GCC documentation:
> If the register is a call-saved register, call ABI is affected: the
> register will not be restored in function epilogue sequences after the
> variable has been assigned. Therefore, functions cannot safely return
> to callers that assume standard ABI.
When our position independent VDSO is built for the n32 or n64 ABIs all
functions it exposes should be preserving the value of $gp/$28 for their
caller, but in the presence of the __current_thread_info global register
variable GCC stops doing so & simply clobbers $gp/$28 when calculating
the address of the GOT.
In cases where the VDSO returns success this problem will typically be
masked by the caller in libc returning & restoring $gp/$28 itself, but
that is by no means guaranteed. In cases where the VDSO returns an error
libc will typically contain a fallback path which will now fail
(typically with a bad memory access) if it attempts anything which
relies upon the value of $gp/$28 - eg. accessing anything via the GOT.
One fix for this would be to move the declaration of
__current_thread_info inside the current_thread_info() function,
demoting it from global register variable to local register variable &
avoiding inadvertently creating a non-standard calling ABI for the VDSO.
Unfortunately this causes issues for clang, which doesn't support local
register variables as pointed out by commit fe92da0f355e ("MIPS: Changed
current_thread_info() to an equivalent supported by both clang and GCC")
which introduced the global register variable before we had a VDSO to
worry about.
Instead, fix this by continuing to use the global register variable for
the kernel proper but declare __current_thread_info as a simple extern
variable when building the VDSO. It should never be referenced, and will
cause a link error if it is. This resolves the calling convention issue
for the VDSO without having any impact upon the build of the kernel
itself for either clang or gcc.
Linus Torvalds [Fri, 3 Jan 2020 00:39:51 +0000 (16:39 -0800)]
Merge tag 'pstore-v5.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull pstore bug fixes from Kees Cook:
- always reset circular buffer state when writing new dump (Aleksandr
Yashkin)
- fix rare error-path memory leak (Kees Cook)
* tag 'pstore-v5.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
pstore/ram: Write new dumps to start of recycled zones
pstore/ram: Fix error-path memory leak in persistent_ram_new() callers
This reverts commit 8243186f0cc7 ("fs: remove ksys_dup()") and the
subsequent fix for it in commit 2d3145f8d280 ("early init: fix error
handling when opening /dev/console").
Trying to use filp_open() and f_dupfd() instead of pseudo-syscalls
caused more trouble than what is worth it: it requires accessing vfs
internals and it turns out there were other bugs in it too.
In particular, the file reference counting was wrong - because unlike
the original "open+2*dup" sequence it used "filp_open+3*f_dupfd" and
thus had an extra leaked file reference.
That in turn then caused odd problems with Androidx86 long after boot
becaue of how the extra reference to the console kept the session active
even after all file descriptors had been closed.
Arnd Bergmann [Wed, 11 Dec 2019 13:39:28 +0000 (14:39 +0100)]
gcc-plugins: make it possible to disable CONFIG_GCC_PLUGINS again
I noticed that randconfig builds with gcc no longer produce a lot of
ccache hits, unlike with clang, and traced this back to plugins
now being enabled unconditionally if they are supported.
I am now working around this by adding
export CCACHE_COMPILERCHECK=/usr/bin/size -A %compiler%
to my top-level Makefile. This changes the heuristic that ccache uses
to determine whether the plugins are the same after a 'make clean'.
However, it also seems that being able to just turn off the plugins is
generally useful, at least for build testing it adds noticeable overhead
but does not find a lot of bugs additional bugs, and may be easier for
ccache users than my workaround.
Sargun Dhillon [Mon, 30 Dec 2019 20:38:11 +0000 (12:38 -0800)]
selftests/seccomp: Catch garbage on SECCOMP_IOCTL_NOTIF_RECV
This adds logic to the user_notification_basic test to set a member
of struct seccomp_notif to an invalid value to ensure that the kernel
returns EINVAL if any of the struct seccomp_notif members are set to
invalid values.
Sargun Dhillon [Sun, 29 Dec 2019 06:24:50 +0000 (22:24 -0800)]
seccomp: Check that seccomp_notif is zeroed out by the user
This patch is a small change in enforcement of the uapi for
SECCOMP_IOCTL_NOTIF_RECV ioctl. Specifically, the datastructure which
is passed (seccomp_notif) must be zeroed out. Previously any of its
members could be set to nonsense values, and we would ignore it.
This ensures all fields are set to their zero value.
Sargun Dhillon [Sun, 29 Dec 2019 06:24:49 +0000 (22:24 -0800)]
selftests/seccomp: Zero out seccomp_notif
The seccomp_notif structure should be zeroed out prior to calling the
SECCOMP_IOCTL_NOTIF_RECV ioctl. Previously, the kernel did not check
whether these structures were zeroed out or not, so these worked.
This patch zeroes out the seccomp_notif data structure prior to calling
the ioctl.
Sargun Dhillon [Mon, 30 Dec 2019 20:35:03 +0000 (12:35 -0800)]
samples/seccomp: Zero out members based on seccomp_notif_sizes
The sizes by which seccomp_notif and seccomp_notif_resp are allocated are
based on the SECCOMP_GET_NOTIF_SIZES ioctl. This allows for graceful
extension of these datastructures. If userspace zeroes out the
datastructure based on its version, and it is lagging behind the kernel's
version, it will end up sending trailing garbage. On the other hand,
if it is ahead of the kernel version, it will write extra zero space,
and potentially cause corruption.
pstore/ram: Write new dumps to start of recycled zones
The ram_core.c routines treat przs as circular buffers. When writing a
new crash dump, the old buffer needs to be cleared so that the new dump
doesn't end up in the wrong place (i.e. at the end).
The solution to this problem is to reset the circular buffer state before
writing a new Oops dump.
John Johansen [Wed, 18 Dec 2019 19:04:07 +0000 (11:04 -0800)]
apparmor: only get a label reference if the fast path check fails
The common fast path check can be done under rcu_read_lock() and
doesn't need a reference count on the label. Only take a reference
count if entering the slow path.
Fixes reported hackbench regression
- sha1 79e178a57dae ("Merge tag 'apparmor-pr-2019-12-03' of
git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor")
hackbench -l (256000/#grp) -g #grp
128 groups 19.679 ±0.90%
- previous sha1 01d1dff64662 ("Merge tag 's390-5.5-2' of
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux")
hackbench -l (256000/#grp) -g #grp
128 groups 3.1689 ±3.04%
Reported-by: Vincent Guittot <[email protected]> Tested-by: Vincent Guittot <[email protected]> Tested-by: Sebastian Andrzej Siewior <[email protected]> Fixes: bce4e7e9c45e ("apparmor: reduce rcu_read_lock scope for aa_file_perm mediation") Signed-off-by: John Johansen <[email protected]>
With commit df323337e507 ("apparmor: Use a memory pool instead per-CPU
caches, 2019-05-03"), AppArmor code was converted to use memory pools. In
that conversion, a bug snuck into the code that polices bind mounts that
causes all bind mounts to fail with -ENOMEM, as we erroneously error out
if `aa_get_buffer` returns a pointer instead of erroring out when it
does _not_ return a valid pointer.
Fix the issue by correctly checking for valid pointers returned by
`aa_get_buffer` to fix bind mounts with AppArmor.
Fixes: df323337e507 ("apparmor: Use a memory pool instead per-CPU caches") Signed-off-by: Patrick Steinhardt <[email protected]> Signed-off-by: John Johansen <[email protected]>
Per confirmation with RLC firmware team, the RLC should
be unhalted after all RLC related firmwares uploaded.
However, in fact the RLC is unhalted immediately after
RLCG firmware uploaded. And that may causes unexpected
PSP hang on loading the succeeding RLC save restore
list related firmwares.
So, we correct the firmware loading sequence to load
RLC save restore list related firmwares before RLCG
ucode. That will help to get around this issue.