powerpc/64s: Machine check handle ifetch from foreign real address for POWER9
authorNicholas Piggin <npiggin@gmail.com>
Mon, 29 May 2017 06:26:44 +0000 (16:26 +1000)
committerMichael Ellerman <mpe@ellerman.id.au>
Tue, 6 Jun 2017 11:17:15 +0000 (21:17 +1000)
The i-side 0111b machine check, which is "Instruction Fetch to foreign
address space", was missed by 7b9f71f974 ("powerpc/64s: POWER9 machine
check handler").

    The POWER9 processor core considers host real addresses with a
    nonzero value in RA(8:12) as foreign address space, accessible only
    by the copy and paste instructions. The copy and paste instruction
    pair can be used to invoke the Nest accelerators via the Virtual
    Accelerator Switchboard (VAS).

It is an error for any regular load/store or ifetch to go to a foreign
addresses. When relocation is on, this causes an MMU exception. When
relocation is off, a machine check exception. It is possible to trigger
this machine check by branching to a foreign address with MSR[IR]=0.

Fixes: 7b9f71f974a1 ("powerpc/64s: POWER9 machine check handler")
Reported-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
arch/powerpc/include/asm/mce.h
arch/powerpc/kernel/mce.c
arch/powerpc/kernel/mce_power.c

index 81eff8631434df85b9c89fdf7f4c75a78b3b98cf..190d69a7f7010d13b9533e4b338f551e4917f7f1 100644 (file)
@@ -90,13 +90,14 @@ enum MCE_UserErrorType {
 enum MCE_RaErrorType {
        MCE_RA_ERROR_INDETERMINATE = 0,
        MCE_RA_ERROR_IFETCH = 1,
-       MCE_RA_ERROR_PAGE_TABLE_WALK_IFETCH = 2,
-       MCE_RA_ERROR_PAGE_TABLE_WALK_IFETCH_FOREIGN = 3,
-       MCE_RA_ERROR_LOAD = 4,
-       MCE_RA_ERROR_STORE = 5,
-       MCE_RA_ERROR_PAGE_TABLE_WALK_LOAD_STORE = 6,
-       MCE_RA_ERROR_PAGE_TABLE_WALK_LOAD_STORE_FOREIGN = 7,
-       MCE_RA_ERROR_LOAD_STORE_FOREIGN = 8,
+       MCE_RA_ERROR_IFETCH_FOREIGN = 2,
+       MCE_RA_ERROR_PAGE_TABLE_WALK_IFETCH = 3,
+       MCE_RA_ERROR_PAGE_TABLE_WALK_IFETCH_FOREIGN = 4,
+       MCE_RA_ERROR_LOAD = 5,
+       MCE_RA_ERROR_STORE = 6,
+       MCE_RA_ERROR_PAGE_TABLE_WALK_LOAD_STORE = 7,
+       MCE_RA_ERROR_PAGE_TABLE_WALK_LOAD_STORE_FOREIGN = 8,
+       MCE_RA_ERROR_LOAD_STORE_FOREIGN = 9,
 };
 
 enum MCE_LinkErrorType {
index 5f9eada3519b2bd18e51a267a5e01e442773a7c3..92f18587569410e169cb8dfdba83aaeb15de2697 100644 (file)
@@ -268,6 +268,7 @@ void machine_check_print_event_info(struct machine_check_event *evt,
        static const char *mc_ra_types[] = {
                "Indeterminate",
                "Instruction fetch (bad)",
+               "Instruction fetch (foreign)",
                "Page table walk ifetch (bad)",
                "Page table walk ifetch (foreign)",
                "Load (bad)",
index f913139bb0c2c9cdd67a20514a453e0b223c314b..d24e689e893f0c625e5cfc8f2f00e44341352436 100644 (file)
@@ -236,6 +236,9 @@ static const struct mce_ierror_table mce_p9_ierror_table[] = {
 { 0x00000000081c0000, 0x0000000000180000, true,
   MCE_ERROR_TYPE_UE,  MCE_UE_ERROR_PAGE_TABLE_WALK_IFETCH,
   MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
+{ 0x00000000081c0000, 0x00000000001c0000, true,
+  MCE_ERROR_TYPE_RA,  MCE_RA_ERROR_IFETCH_FOREIGN,
+  MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },
 { 0x00000000081c0000, 0x0000000008000000, true,
   MCE_ERROR_TYPE_LINK,MCE_LINK_ERROR_IFETCH_TIMEOUT,
   MCE_INITIATOR_CPU,  MCE_SEV_ERROR_SYNC, },