Messages in this thread | | | Date | Wed, 8 Feb 2023 15:11:21 +0800 | From | Yujie Liu <> | Subject | Re: arch/x86/kvm/mmu/paging_tmpl.h:106:24: sparse: sparse: cast truncates bits from constant value (ffffffffff000 becomes fffff000) |
| |
Hi Sean,
On Tue, Feb 07, 2023 at 11:34:11PM +0000, Sean Christopherson wrote: > On Tue, Feb 07, 2023, kernel test robot wrote: > > Hi Sean, > > > > FYI, the error/warning was bisected to this commit, please ignore it if it's irrelevant. > > Is there a way to mark this as "working as intended"? The truncation is intentional. > I've been ignoring the reports, but they just keep coming :-)
Sorry for reporting this warning repeatedly. We've added it to the ignore list for this particular commit.
Best Regards, Yujie
> > tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master > > head: d2d11f342b179f1894a901f143ec7c008caba43e > > commit: 70e41c31bc7776b262cd9f524df3dfc2b5869a0a KVM: x86/mmu: Use common logic for computing the 32/64-bit base PA mask > > date: 8 months ago > > config: x86_64-randconfig-s023-20230206 (https://download.01.org/0day-ci/archive/20230207/202302070638.iEBPQ4gL-lkp@intel.com/config) > > compiler: gcc-11 (Debian 11.3.0-8) 11.3.0 > > reproduce: > > # apt-get install sparse > > # sparse version: v0.6.4-39-gce1a6720-dirty > > # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=70e41c31bc7776b262cd9f524df3dfc2b5869a0a > > git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git > > git fetch --no-tags linus master > > git checkout 70e41c31bc7776b262cd9f524df3dfc2b5869a0a > > # save the config file > > mkdir build_dir && cp config build_dir/.config > > make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=x86_64 olddefconfig > > make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=x86_64 SHELL=/bin/bash arch/x86/kvm/ > > > > If you fix the issue, kindly add following tag where applicable > > | Reported-by: kernel test robot <lkp@intel.com> > > > > sparse warnings: (new ones prefixed by >>) > > arch/x86/kvm/mmu/mmu.c:610:9: sparse: sparse: context imbalance in 'walk_shadow_page_lockless_begin' - different lock contexts for basic block > > arch/x86/kvm/mmu/mmu.c: note: in included file (through include/linux/rbtree.h, include/linux/mm_types.h, arch/x86/kvm/irq.h): > > include/linux/rcupdate.h:726:9: sparse: sparse: context imbalance in 'walk_shadow_page_lockless_end' - unexpected unlock > > arch/x86/kvm/mmu/mmu.c:2550:9: sparse: sparse: context imbalance in 'mmu_try_to_unsync_pages' - different lock contexts for basic block > > arch/x86/kvm/mmu/mmu.c: note: in included file: > > >> arch/x86/kvm/mmu/paging_tmpl.h:106:24: sparse: sparse: cast truncates bits from constant value (ffffffffff000 becomes fffff000) > > arch/x86/kvm/mmu/paging_tmpl.h:426:24: sparse: sparse: cast truncates bits from constant value (ffffffffff000 becomes fffff000) > > arch/x86/kvm/mmu/mmu.c:4618:57: sparse: sparse: cast truncates bits from constant value (ffffff33 becomes 33) > > arch/x86/kvm/mmu/mmu.c:4620:56: sparse: sparse: cast truncates bits from constant value (ffffff0f becomes f) > > arch/x86/kvm/mmu/mmu.c:4622:57: sparse: sparse: cast truncates bits from constant value (ffffff55 becomes 55) > > > > vim +106 arch/x86/kvm/mmu/paging_tmpl.h > > > > b3fcdb04a98035 arch/x86/kvm/mmu/paging_tmpl.h Sean Christopherson 2022-06-14 103 > > e04da980c35d75 arch/x86/kvm/paging_tmpl.h Joerg Roedel 2009-07-27 104 static gfn_t gpte_to_gfn_lvl(pt_element_t gpte, int lvl) > > 5fb07ddb183eb4 drivers/kvm/paging_tmpl.h Avi Kivity 2007-11-21 105 { > > e04da980c35d75 arch/x86/kvm/paging_tmpl.h Joerg Roedel 2009-07-27 @106 return (gpte & PT_LVL_ADDR_MASK(lvl)) >> PAGE_SHIFT; > > 5fb07ddb183eb4 drivers/kvm/paging_tmpl.h Avi Kivity 2007-11-21 107 } > > 5fb07ddb183eb4 drivers/kvm/paging_tmpl.h Avi Kivity 2007-11-21 108 > > > > :::::: The code at line 106 was first introduced by commit > > :::::: e04da980c35d75fa050ba4009ad99025432d8d7d KVM: MMU: make page walker aware of mapping levels > > > > :::::: TO: Joerg Roedel <joerg.roedel@amd.com> > > :::::: CC: Avi Kivity <avi@redhat.com> > > > > -- > > 0-DAY CI Kernel Test Service > > https://github.com/intel/lkp-tests >
| |