[PATCH v9 04/10] sparc64: Add HV fault type handlers for ADI related faults

From: Khalid Aziz
Date: Fri Oct 20 2017 - 12:58:38 EST


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.aziz@xxxxxxxxxx>
Cc: Khalid Aziz <khalid@xxxxxxxxxxxxxx>
---
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 0fe0eed3cecb..7775d011691c 100644
--- a/arch/sparc/kernel/traps_64.c
+++ b/arch/sparc/kernel/traps_64.c
@@ -352,12 +352,35 @@ void sun4v_data_access_exception(struct pt_regs *regs, unsigned long addr, unsig
regs->tpc &= 0xffffffff;
regs->tnpc &= 0xffffffff;
}
- 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