Re: [PATCH v3 8/8] KVM: x86/mmu: Lazily allocate memslot rmaps
From: kernel test robot
Date: Thu May 06 2021 - 21:11:39 EST
Hi Ben,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on kvm/queue]
[also build test WARNING on tip/master linus/master next-20210506]
[cannot apply to linux/master v5.12]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Ben-Gardon/Lazily-allocate-memslot-rmaps/20210507-024533
base: https://git.kernel.org/pub/scm/virt/kvm/kvm.git queue
config: x86_64-randconfig-s021-20210506 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce:
# apt-get install sparse
# sparse version: v0.6.3-341-g8af24329-dirty
# https://github.com/0day-ci/linux/commit/43798461d3f4a38ef487d9c626dd0fb13e403328
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Ben-Gardon/Lazily-allocate-memslot-rmaps/20210507-024533
git checkout 43798461d3f4a38ef487d9c626dd0fb13e403328
# save the attached .config to linux build tree
make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' W=1 ARCH=x86_64
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>
sparse warnings: (new ones prefixed by >>)
arch/x86/kvm/x86.c:10926:17: sparse: sparse: incompatible types in comparison expression (different address spaces):
arch/x86/kvm/x86.c:10926:17: sparse: struct kvm_rmap_head [noderef] __rcu *
arch/x86/kvm/x86.c:10926:17: sparse: struct kvm_rmap_head *
arch/x86/kvm/x86.c: note: in included file (through include/linux/notifier.h, include/linux/memory_hotplug.h, include/linux/mmzone.h, ...):
include/linux/srcu.h:182:9: sparse: sparse: context imbalance in 'vcpu_enter_guest' - unexpected unlock
>> arch/x86/kvm/x86.c:10971:29: sparse: sparse: marked inline, but without a definition
vim +10971 arch/x86/kvm/x86.c
db3fe4eb45f355 Takuya Yoshikawa 2012-02-08 10913
11bb59d1c3e83b Ben Gardon 2021-05-06 10914 static int alloc_memslot_rmap(struct kvm_memory_slot *slot,
11bb59d1c3e83b Ben Gardon 2021-05-06 10915 unsigned long npages)
11bb59d1c3e83b Ben Gardon 2021-05-06 10916 {
11bb59d1c3e83b Ben Gardon 2021-05-06 10917 int i;
11bb59d1c3e83b Ben Gardon 2021-05-06 10918
11bb59d1c3e83b Ben Gardon 2021-05-06 10919 for (i = 0; i < KVM_NR_PAGE_SIZES; ++i) {
11bb59d1c3e83b Ben Gardon 2021-05-06 10920 int lpages;
11bb59d1c3e83b Ben Gardon 2021-05-06 10921 int level = i + 1;
11bb59d1c3e83b Ben Gardon 2021-05-06 10922
11bb59d1c3e83b Ben Gardon 2021-05-06 10923 lpages = gfn_to_index(slot->base_gfn + npages - 1,
11bb59d1c3e83b Ben Gardon 2021-05-06 10924 slot->base_gfn, level) + 1;
11bb59d1c3e83b Ben Gardon 2021-05-06 10925
dd56af97c1d2b2 Ben Gardon 2021-05-06 @10926 rcu_assign_pointer(slot->arch.rmap[i],
11bb59d1c3e83b Ben Gardon 2021-05-06 10927 kvcalloc(lpages, sizeof(*slot->arch.rmap[i]),
dd56af97c1d2b2 Ben Gardon 2021-05-06 10928 GFP_KERNEL_ACCOUNT));
11bb59d1c3e83b Ben Gardon 2021-05-06 10929 if (!slot->arch.rmap[i])
11bb59d1c3e83b Ben Gardon 2021-05-06 10930 goto out_free;
11bb59d1c3e83b Ben Gardon 2021-05-06 10931 }
11bb59d1c3e83b Ben Gardon 2021-05-06 10932
11bb59d1c3e83b Ben Gardon 2021-05-06 10933 return 0;
11bb59d1c3e83b Ben Gardon 2021-05-06 10934
11bb59d1c3e83b Ben Gardon 2021-05-06 10935 out_free:
11bb59d1c3e83b Ben Gardon 2021-05-06 10936 free_memslot_rmap(slot);
11bb59d1c3e83b Ben Gardon 2021-05-06 10937 return -ENOMEM;
11bb59d1c3e83b Ben Gardon 2021-05-06 10938 }
11bb59d1c3e83b Ben Gardon 2021-05-06 10939
43798461d3f4a3 Ben Gardon 2021-05-06 10940 int alloc_all_memslots_rmaps(struct kvm *kvm)
43798461d3f4a3 Ben Gardon 2021-05-06 10941 {
43798461d3f4a3 Ben Gardon 2021-05-06 10942 struct kvm_memslots *slots;
43798461d3f4a3 Ben Gardon 2021-05-06 10943 struct kvm_memory_slot *slot;
43798461d3f4a3 Ben Gardon 2021-05-06 10944 int r = 0;
43798461d3f4a3 Ben Gardon 2021-05-06 10945 int i;
43798461d3f4a3 Ben Gardon 2021-05-06 10946
43798461d3f4a3 Ben Gardon 2021-05-06 10947 if (kvm_memslots_have_rmaps(kvm))
43798461d3f4a3 Ben Gardon 2021-05-06 10948 return 0;
43798461d3f4a3 Ben Gardon 2021-05-06 10949
43798461d3f4a3 Ben Gardon 2021-05-06 10950 mutex_lock(&kvm->slots_arch_lock);
43798461d3f4a3 Ben Gardon 2021-05-06 10951 for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) {
43798461d3f4a3 Ben Gardon 2021-05-06 10952 slots = __kvm_memslots(kvm, i);
43798461d3f4a3 Ben Gardon 2021-05-06 10953 kvm_for_each_memslot(slot, slots) {
43798461d3f4a3 Ben Gardon 2021-05-06 10954 r = alloc_memslot_rmap(slot, slot->npages);
43798461d3f4a3 Ben Gardon 2021-05-06 10955 if (r) {
43798461d3f4a3 Ben Gardon 2021-05-06 10956 mutex_unlock(&kvm->slots_arch_lock);
43798461d3f4a3 Ben Gardon 2021-05-06 10957 return r;
43798461d3f4a3 Ben Gardon 2021-05-06 10958 }
43798461d3f4a3 Ben Gardon 2021-05-06 10959 }
43798461d3f4a3 Ben Gardon 2021-05-06 10960 }
43798461d3f4a3 Ben Gardon 2021-05-06 10961
43798461d3f4a3 Ben Gardon 2021-05-06 10962 /*
43798461d3f4a3 Ben Gardon 2021-05-06 10963 * memslots_have_rmaps is set and read in different lock contexts,
43798461d3f4a3 Ben Gardon 2021-05-06 10964 * so protect it with smp_load/store.
43798461d3f4a3 Ben Gardon 2021-05-06 10965 */
43798461d3f4a3 Ben Gardon 2021-05-06 10966 smp_store_release(&kvm->arch.memslots_have_rmaps, true);
43798461d3f4a3 Ben Gardon 2021-05-06 10967 mutex_unlock(&kvm->slots_arch_lock);
43798461d3f4a3 Ben Gardon 2021-05-06 10968 return 0;
43798461d3f4a3 Ben Gardon 2021-05-06 10969 }
43798461d3f4a3 Ben Gardon 2021-05-06 10970
fac0d516d29b67 Ben Gardon 2021-05-06 @10971 bool kvm_memslots_have_rmaps(struct kvm *kvm)
fac0d516d29b67 Ben Gardon 2021-05-06 10972 {
43798461d3f4a3 Ben Gardon 2021-05-06 10973 /*
43798461d3f4a3 Ben Gardon 2021-05-06 10974 * memslots_have_rmaps is set and read in different lock contexts,
43798461d3f4a3 Ben Gardon 2021-05-06 10975 * so protect it with smp_load/store.
43798461d3f4a3 Ben Gardon 2021-05-06 10976 */
43798461d3f4a3 Ben Gardon 2021-05-06 10977 return smp_load_acquire(&kvm->arch.memslots_have_rmaps);
fac0d516d29b67 Ben Gardon 2021-05-06 10978 }
fac0d516d29b67 Ben Gardon 2021-05-06 10979
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx
Attachment:
.config.gz
Description: application/gzip