[PATCH v11 04/10] sparc64: Add HV fault type handlers for ADI related faults

[Khalid Aziz]

ADI (Application Data Integrity) feature on M7 and newer processors
adds new fault types for hypervisor - Invalid ASI and MCD disabled.
This patch expands data access exception handler to handle these
faults.

Signed-off-by: Khalid Aziz <khalid.a...@oracle.com>
Cc: Khalid Aziz <kha...@gonehiking.org>
Reviewed-by: Anthony Yznaga <anthony.yzn...@oracle.com>
---
v7:
        - new patch split off from patch 4/4 in v6

 arch/sparc/kernel/traps_64.c | 29 ++++++++++++++++++++++++++---
 1 file changed, 26 insertions(+), 3 deletions(-)

diff --git a/arch/sparc/kernel/traps_64.c b/arch/sparc/kernel/traps_64.c
index fc73baa588f6..d273a65a0a10 100644
--- a/arch/sparc/kernel/traps_64.c
+++ b/arch/sparc/kernel/traps_64.c
@@ -397,12 +397,35 @@ void sun4v_data_access_exception(struct pt_regs *regs, 
unsigned long addr, unsig
        if (is_no_fault_exception(regs))
                return;
 
-       info.si_signo = SIGSEGV;
+       /* MCD (Memory Corruption Detection) disabled trap (TT=0x19) in HV
+        * is vectored thorugh data access exception trap with fault type
+        * set to HV_FAULT_TYPE_MCD_DIS. Check for MCD disabled trap.
+        * Accessing an address with invalid ASI for the address, for
+        * example setting an ADI tag on an address with ASI_MCD_PRIMARY
+        * when TTE.mcd is not set for the VA, is also vectored into
+        * kerbel by HV as data access exception with fault type set to
+        * HV_FAULT_TYPE_INV_ASI.
+        */
        info.si_errno = 0;
-       info.si_code = SEGV_MAPERR;
        info.si_addr = (void __user *) addr;
        info.si_trapno = 0;
-       force_sig_info(SIGSEGV, &info, current);
+       switch (type) {
+       case HV_FAULT_TYPE_INV_ASI:
+               info.si_signo = SIGILL;
+               info.si_code = ILL_ILLADR;
+               force_sig_info(SIGILL, &info, current);
+               break;
+       case HV_FAULT_TYPE_MCD_DIS:
+               info.si_signo = SIGSEGV;
+               info.si_code = SEGV_ACCADI;
+               force_sig_info(SIGSEGV, &info, current);
+               break;
+       default:
+               info.si_signo = SIGSEGV;
+               info.si_code = SEGV_MAPERR;
+               force_sig_info(SIGSEGV, &info, current);
+               break;
+       }
 }
 
 void sun4v_data_access_exception_tl1(struct pt_regs *regs, unsigned long addr, 
unsigned long type_ctx)
-- 
2.11.0