| Message ID | 20220117084618.442906-1-zhenzhong.duan@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v3] x86: Assign a canonical address before execute invpcid | expand |
On 1/17/22 09:46, Zhenzhong Duan wrote: > Accidently we see pcid test failed as INVPCID_DESC[127:64] is > uninitialized before execute invpcid. > > According to Intel spec: "#GP If INVPCID_TYPE is 0 and the linear > address in INVPCID_DESC[127:64] is not canonical." > > By zeroing the whole invpcid_desc structure, ensure the address > canonical and reserved bit zero in desc. > > By this chance change invpcid_desc to be 128bit in size no matter > in 64bit or 32bit mode to match the description in spec, even > though this test case is 64bit only. > > Fixes: b44d84dae10c ("Add PCID/INVPCID test") > Suggested-by: Sean Christopherson <seanjc@google.com> > Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com> > Reviewed-by: Sean Christopherson <seanjc@google.com> > --- > v3: update patch description > > x86/pcid.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/x86/pcid.c b/x86/pcid.c > index 527a4a9..80a4611 100644 > --- a/x86/pcid.c > +++ b/x86/pcid.c > @@ -5,9 +5,9 @@ > #include "desc.h" > > struct invpcid_desc { > - unsigned long pcid : 12; > - unsigned long rsv : 52; > - unsigned long addr : 64; > + u64 pcid : 12; > + u64 rsv : 52; > + u64 addr : 64; > }; > > static int write_cr0_checking(unsigned long val) > @@ -73,12 +73,12 @@ static void test_invpcid_enabled(int pcid_enabled) > int passed = 0, i; > ulong cr4 = read_cr4(); > struct invpcid_desc desc; > - desc.rsv = 0; > + > + memset(&desc, 0, sizeof(desc)); > > /* try executing invpcid when CR4.PCIDE=0, desc.pcid=0 and type=0..3 > * no exception expected > */ > - desc.pcid = 0; > for (i = 0; i < 4; i++) { > if (invpcid_checking(i, &desc) != 0) > goto report; Queued, thanks. Paolo
diff --git a/x86/pcid.c b/x86/pcid.c index 527a4a9..80a4611 100644 --- a/x86/pcid.c +++ b/x86/pcid.c @@ -5,9 +5,9 @@ #include "desc.h" struct invpcid_desc { - unsigned long pcid : 12; - unsigned long rsv : 52; - unsigned long addr : 64; + u64 pcid : 12; + u64 rsv : 52; + u64 addr : 64; }; static int write_cr0_checking(unsigned long val) @@ -73,12 +73,12 @@ static void test_invpcid_enabled(int pcid_enabled) int passed = 0, i; ulong cr4 = read_cr4(); struct invpcid_desc desc; - desc.rsv = 0; + + memset(&desc, 0, sizeof(desc)); /* try executing invpcid when CR4.PCIDE=0, desc.pcid=0 and type=0..3 * no exception expected */ - desc.pcid = 0; for (i = 0; i < 4; i++) { if (invpcid_checking(i, &desc) != 0) goto report;
Accidently we see pcid test failed as INVPCID_DESC[127:64] is uninitialized before execute invpcid. According to Intel spec: "#GP If INVPCID_TYPE is 0 and the linear address in INVPCID_DESC[127:64] is not canonical." By zeroing the whole invpcid_desc structure, ensure the address canonical and reserved bit zero in desc. By this chance change invpcid_desc to be 128bit in size no matter in 64bit or 32bit mode to match the description in spec, even though this test case is 64bit only. Fixes: b44d84dae10c ("Add PCID/INVPCID test") Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com> Reviewed-by: Sean Christopherson <seanjc@google.com> --- v3: update patch description x86/pcid.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)