Re: [Crash-utility] The problems when running SuSE 12 on VirtualBox

I was originally thinking about the same as yourself but decided against it due to thinking first that, in English, QUIET is a bit abstract for "don't try to switch devmem source" as well as avoid output. Plus, if any other readmem() that's QUIET fails READ_ERROR for any random reason and devmem_is_restricted() will fail a switch_to_proc_kcore() would have resolved it then that caller's use of QUIET will prevent devmem_is_restricted() being tried and it won't switch_to_proc_kcore(). I admit that means the status of devmem_is_restricted() has changed between initialization and now, but it's a live environment with it's own behavior. Due to the small number of error_handle flags here's one that uses the best of your idea without expanding the meaning of the word QUIET. It adds another flag for the sole purpose of saying "don't try to switch devmem source this time" and it avoids all the overhead I originally had. The name for the flag is long enough that the value tab alignment doesn't match with the other flags (I can't think of a shorter name for the flag but maybe you can). I chose not to appear to make three extra lines of changes just to expand the tab alignment on the other flags. It also leaves PRINT_ERROR_MESSAGE over-riding QUIET as at present but I don't have a preference for that -d8 has it's useful moments:

diff --git a/defs.h b/defs.h index b0cdd42..29f46b4 100644 --- a/defs.h +++ b/defs.h @@ -328,6 +328,7 @@ struct number_option { #define HEX_BIAS (0x8) #define LONG_LONG (0x10) #define RETURN_PARTIAL (0x20) +#define NO_DEVMEM_SWITCH (0x40) #define SEEK_ERROR (-1) #define READ_ERROR (-2) diff --git a/memory.c b/memory.c index 72218e7..b4629a6 100644 --- a/memory.c +++ b/memory.c @@ -2204,14 +2204,14 @@ readmem(ulonglong addr, int memtype, void *buffer, long size, goto readmem_error; case READ_ERROR: - if (PRINT_ERROR_MESSAGE) { - if ((pc->flags & DEVMEM) && (kt->flags & PRE_KERNEL_INIT) && - devmem_is_restricted() && switch_to_proc_kcore()) - return(readmem(addr, memtype, bufptr, size, - type, error_handle)); + if (PRINT_ERROR_MESSAGE) error(INFO, READ_ERRMSG, memtype_string(memtype, 0), addr, type); - } - goto readmem_error; + + if ((pc->flags & DEVMEM) && (kt->flags & PRE_KERNEL_INIT) && + !(error_handle & NO_DEVMEM_SWITCH) && devmem_is_restricted() && switch_to_proc_kcore()) + return(readmem(addr, memtype, bufptr, size, + type, error_handle)); + goto readmem_error; case PAGE_EXCLUDED: RETURN_ON_PARTIAL_READ(); @@ -2410,16 +2410,16 @@ devmem_is_restricted(void) if (machine_type("X86") || machine_type("X86_64")) { if (readmem(255*PAGESIZE(), PHYSADDR, &tmp, sizeof(long), "devmem_is_allowed - pfn 255", - QUIET|RETURN_ON_ERROR) && + QUIET|RETURN_ON_ERROR|NO_DEVMEM_SWITCH) && !(readmem(257*PAGESIZE(), PHYSADDR, &tmp, sizeof(long), "devmem_is_allowed - pfn 257", - QUIET|RETURN_ON_ERROR))) + QUIET|RETURN_ON_ERROR|NO_DEVMEM_SWITCH))) restricted = TRUE; } if (kernel_symbol_exists("jiffies") && !readmem(symbol_value("jiffies"), KVADDR, &tmp, sizeof(ulong), "devmem_is_allowed - jiffies", - QUIET|RETURN_ON_ERROR)) + QUIET|RETURN_ON_ERROR|NO_DEVMEM_SWITCH)) restricted = TRUE; if (restricted) -- Crash-utility mailing list Crash-utility(a)redhat.com https://www.redhat.com/mailman/listinfo/crash-utility