diff options
| author | Arnd Bergmann <arnd@arndb.de> | 2019-07-12 11:12:30 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-08-06 19:05:22 +0200 |
| commit | 9e5ba38934b51b82e1c49092a0f9ccba5b3e7fd7 (patch) | |
| tree | 65d384edf0ed1d140620c8c64194b5329f282fb5 /arch/x86/kvm/mmu.c | |
| parent | 120704bef9cc32cceab7e1afb7b8d7fb4c44292a (diff) | |
x86: kvm: avoid constant-conversion warning
[ Upstream commit a6a6d3b1f867d34ba5bd61aa7bb056b48ca67cff ]
clang finds a contruct suspicious that converts an unsigned
character to a signed integer and back, causing an overflow:
arch/x86/kvm/mmu.c:4605:39: error: implicit conversion from 'int' to 'u8' (aka 'unsigned char') changes value from -205 to 51 [-Werror,-Wconstant-conversion]
u8 wf = (pfec & PFERR_WRITE_MASK) ? ~w : 0;
~~ ^~
arch/x86/kvm/mmu.c:4607:38: error: implicit conversion from 'int' to 'u8' (aka 'unsigned char') changes value from -241 to 15 [-Werror,-Wconstant-conversion]
u8 uf = (pfec & PFERR_USER_MASK) ? ~u : 0;
~~ ^~
arch/x86/kvm/mmu.c:4609:39: error: implicit conversion from 'int' to 'u8' (aka 'unsigned char') changes value from -171 to 85 [-Werror,-Wconstant-conversion]
u8 ff = (pfec & PFERR_FETCH_MASK) ? ~x : 0;
~~ ^~
Add an explicit cast to tell clang that everything works as
intended here.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://github.com/ClangBuiltLinux/linux/issues/95
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'arch/x86/kvm/mmu.c')
| -rw-r--r-- | arch/x86/kvm/mmu.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index f97b533bc6e6..87a0601b1c20 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -4313,11 +4313,11 @@ static void update_permission_bitmask(struct kvm_vcpu *vcpu, */ /* Faults from writes to non-writable pages */ - u8 wf = (pfec & PFERR_WRITE_MASK) ? ~w : 0; + u8 wf = (pfec & PFERR_WRITE_MASK) ? (u8)~w : 0; /* Faults from user mode accesses to supervisor pages */ - u8 uf = (pfec & PFERR_USER_MASK) ? ~u : 0; + u8 uf = (pfec & PFERR_USER_MASK) ? (u8)~u : 0; /* Faults from fetches of non-executable pages*/ - u8 ff = (pfec & PFERR_FETCH_MASK) ? ~x : 0; + u8 ff = (pfec & PFERR_FETCH_MASK) ? (u8)~x : 0; /* Faults from kernel mode fetches of user pages */ u8 smepf = 0; /* Faults from kernel mode accesses of user pages */ |