| Message ID | 20210707183616.5620-9-brijesh.singh@amd.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Delegated to: | Herbert Xu |
| Headers | show |
| Series | Add AMD Secure Nested Paging (SEV-SNP) Hypervisor Support | expand |
On Wed, Jul 07, 2021, Brijesh Singh wrote: > Bit 31 in the page fault-error bit will be set when processor encounters > an RMP violation. > > While at it, use the BIT() macro. > > Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> > --- > arch/x86/include/asm/trap_pf.h | 18 +++++++++++------- > arch/x86/mm/fault.c | 1 + > 2 files changed, 12 insertions(+), 7 deletions(-) > > diff --git a/arch/x86/include/asm/trap_pf.h b/arch/x86/include/asm/trap_pf.h > index 10b1de500ab1..29f678701753 100644 > --- a/arch/x86/include/asm/trap_pf.h > +++ b/arch/x86/include/asm/trap_pf.h > @@ -2,6 +2,8 @@ > #ifndef _ASM_X86_TRAP_PF_H > #define _ASM_X86_TRAP_PF_H > > +#include <vdso/bits.h> /* BIT() macro */ What are people's thoughts on using linux/bits.h instead of vdso.bits.h, even though the vDSO version is technically sufficient? Seeing the "vdso" reference definitely made me blink slowly a few times. > + > /* > * Page fault error code bits: > * > @@ -12,15 +14,17 @@ > * bit 4 == 1: fault was an instruction fetch > * bit 5 == 1: protection keys block access > * bit 15 == 1: SGX MMU page-fault > + * bit 31 == 1: fault was an RMP violation > */ > enum x86_pf_error_code { > - X86_PF_PROT = 1 << 0, > - X86_PF_WRITE = 1 << 1, > - X86_PF_USER = 1 << 2, > - X86_PF_RSVD = 1 << 3, > - X86_PF_INSTR = 1 << 4, > - X86_PF_PK = 1 << 5, > - X86_PF_SGX = 1 << 15, > + X86_PF_PROT = BIT(0), > + X86_PF_WRITE = BIT(1), > + X86_PF_USER = BIT(2), > + X86_PF_RSVD = BIT(3), > + X86_PF_INSTR = BIT(4), > + X86_PF_PK = BIT(5), > + X86_PF_SGX = BIT(15), > + X86_PF_RMP = BIT(31), > }; > > #endif /* _ASM_X86_TRAP_PF_H */ > diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c > index 1c548ad00752..2715240c757e 100644 > --- a/arch/x86/mm/fault.c > +++ b/arch/x86/mm/fault.c > @@ -545,6 +545,7 @@ show_fault_oops(struct pt_regs *regs, unsigned long error_code, unsigned long ad > !(error_code & X86_PF_PROT) ? "not-present page" : > (error_code & X86_PF_RSVD) ? "reserved bit violation" : > (error_code & X86_PF_PK) ? "protection keys violation" : > + (error_code & X86_PF_RMP) ? "rmp violation" : > "permissions violation"); > > if (!(error_code & X86_PF_USER) && user_mode(regs)) { > -- > 2.17.1 >
On 7/15/21 12:02 PM, Sean Christopherson wrote: >> #ifndef _ASM_X86_TRAP_PF_H >> #define _ASM_X86_TRAP_PF_H >> >> +#include <vdso/bits.h> /* BIT() macro */ > What are people's thoughts on using linux/bits.h instead of vdso.bits.h, even > though the vDSO version is technically sufficient? Seeing the "vdso" reference > definitely made me blink slowly a few times. Ugh, missed that. Yes, that does look very weird. I don't see any reason to use that vdso/ version instead of BIT_ULL(). I suspect I said to use BIT() when I commented on this in a previous round. If so, that was wrong.
diff --git a/arch/x86/include/asm/trap_pf.h b/arch/x86/include/asm/trap_pf.h index 10b1de500ab1..29f678701753 100644 --- a/arch/x86/include/asm/trap_pf.h +++ b/arch/x86/include/asm/trap_pf.h @@ -2,6 +2,8 @@ #ifndef _ASM_X86_TRAP_PF_H #define _ASM_X86_TRAP_PF_H +#include <vdso/bits.h> /* BIT() macro */ + /* * Page fault error code bits: * @@ -12,15 +14,17 @@ * bit 4 == 1: fault was an instruction fetch * bit 5 == 1: protection keys block access * bit 15 == 1: SGX MMU page-fault + * bit 31 == 1: fault was an RMP violation */ enum x86_pf_error_code { - X86_PF_PROT = 1 << 0, - X86_PF_WRITE = 1 << 1, - X86_PF_USER = 1 << 2, - X86_PF_RSVD = 1 << 3, - X86_PF_INSTR = 1 << 4, - X86_PF_PK = 1 << 5, - X86_PF_SGX = 1 << 15, + X86_PF_PROT = BIT(0), + X86_PF_WRITE = BIT(1), + X86_PF_USER = BIT(2), + X86_PF_RSVD = BIT(3), + X86_PF_INSTR = BIT(4), + X86_PF_PK = BIT(5), + X86_PF_SGX = BIT(15), + X86_PF_RMP = BIT(31), }; #endif /* _ASM_X86_TRAP_PF_H */ diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 1c548ad00752..2715240c757e 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -545,6 +545,7 @@ show_fault_oops(struct pt_regs *regs, unsigned long error_code, unsigned long ad !(error_code & X86_PF_PROT) ? "not-present page" : (error_code & X86_PF_RSVD) ? "reserved bit violation" : (error_code & X86_PF_PK) ? "protection keys violation" : + (error_code & X86_PF_RMP) ? "rmp violation" : "permissions violation"); if (!(error_code & X86_PF_USER) && user_mode(regs)) {
Bit 31 in the page fault-error bit will be set when processor encounters an RMP violation. While at it, use the BIT() macro. Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> --- arch/x86/include/asm/trap_pf.h | 18 +++++++++++------- arch/x86/mm/fault.c | 1 + 2 files changed, 12 insertions(+), 7 deletions(-)