kernel_optimize_test/arch
Sean Christopherson 0577d1abe7 KVM: Terminate memslot walks via used_slots
Refactor memslot handling to treat the number of used slots as the de
facto size of the memslot array, e.g. return NULL from id_to_memslot()
when an invalid index is provided instead of relying on npages==0 to
detect an invalid memslot.  Rework the sorting and walking of memslots
in advance of dynamically sizing memslots to aid bisection and debug,
e.g. with luck, a bug in the refactoring will bisect here and/or hit a
WARN instead of randomly corrupting memory.

Alternatively, a global null/invalid memslot could be returned, i.e. so
callers of id_to_memslot() don't have to explicitly check for a NULL
memslot, but that approach runs the risk of introducing difficult-to-
debug issues, e.g. if the global null slot is modified.  Constifying
the return from id_to_memslot() to combat such issues is possible, but
would require a massive refactoring of arch specific code and would
still be susceptible to casting shenanigans.

Add function comments to update_memslots() and search_memslots() to
explicitly (and loudly) state how memslots are sorted.

Opportunistically stuff @hva with a non-canonical value when deleting a
private memslot on x86 to detect bogus usage of the freed slot.

No functional change intended.

Tested-by: Christoffer Dall <christoffer.dall@arm.com>
Tested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:26 +01:00
..
alpha Kbuild updates for v5.6 (2nd) 2020-02-09 16:05:50 -08:00
arc arc: mm: add p?d_leaf() definitions 2020-02-04 03:05:24 +00:00
arm Kbuild updates for v5.6 (2nd) 2020-02-09 16:05:50 -08:00
arm64 Kbuild updates for v5.6 (2nd) 2020-02-09 16:05:50 -08:00
c6x
csky Microblaze patches for 5.6-rc1 2020-02-04 11:58:07 +00:00
h8300
hexagon
ia64 proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
m68k Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu 2020-02-06 08:13:23 +00:00
microblaze Microblaze patches for 5.6-rc1 2020-02-04 11:58:07 +00:00
mips KVM: Provide common implementation for generic dirty log functions 2020-03-16 17:57:24 +01:00
nds32
nios2
openrisc
parisc Merge branch 'parisc-5.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux 2020-02-05 07:29:40 +00:00
powerpc KVM: Terminate memslot walks via used_slots 2020-03-16 17:57:26 +01:00
riscv Microblaze patches for 5.6-rc1 2020-02-04 11:58:07 +00:00
s390 KVM: Ensure validity of memslot with respect to kvm_get_dirty_log() 2020-03-16 17:57:25 +01:00
sh proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
sparc Kbuild updates for v5.6 (2nd) 2020-02-09 16:05:50 -08:00
um proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
unicore32 MPX requires recompiling applications, which requires compiler support. 2020-01-30 16:11:50 -08:00
x86 KVM: Terminate memslot walks via used_slots 2020-03-16 17:57:26 +01:00
xtensa Xtensa updates for v5.6: 2020-02-07 12:22:29 -08:00
.gitignore
Kconfig asm-generic/tlb: provide MMU_GATHER_TABLE_FREE 2020-02-04 03:05:26 +00:00