From 08e08d1330f5d4dd0989bfb1558d85c82254654e Mon Sep 17 00:00:00 2001 From: Bhupesh Sharma Date: Fri, 17 Nov 2017 06:30:41 +0900 Subject: [PATCH 2/2] [PATCH 2/2] Fix 'kernel_version' variable being uninitialized & introduce minor reorganization On executing `makedumpfile --mem-usage /proc/kcore`, it fails currently with the following error message on newer Linux kernels like 4.13.0 or 4.14.0: mem-usage not supported for this kernel. You can try with -f if your kernel's kcore has valid p_paddr makedumpfile Failed. This happens because 'info->kernel_version' is uninitialized in function main(). So when we perform the following check, it fails even though the kernel version is greater than 4.11.0: if (info->kernel_version < KERNEL_VERSION(4, 11, 0) && !info->flag_force) { Fix this by reorganizing the code to: - Add an API to populate the kernel version. - Call this API rather than replicating the open code across other APIs across 'makedumpfile.c' After this patch, '--mem-usage' can be used properly with makedumpfile. Here are the logs I observe on a Fedora 26 ppc64le system: The kernel version is not supported. The makedumpfile operation may be incomplete. TYPE PAGES EXCLUDABLE DESCRIPTION ---------------------------------------------------------------------- ZERO 99 yes Pages filled with zero NON_PRI_CACHE 7817 yes Cache pages without private flag PRI_CACHE 63603 yes Cache pages with private flag USER 4105 yes User process pages FREE 165446 yes Free pages KERN_DATA 6738 no Dumpable kernel data page size: 65536 Total pages on system: 247808 Total size on system: 16240345088 Byte Signed-off-by: Bhupesh Sharma --- makedumpfile.c | 31 ++++++++++++++++++++----------- 1 file changed, 20 insertions(+), 11 deletions(-) diff --git a/makedumpfile-1.6.2/makedumpfile.c b/makedumpfile-1.6.2/makedumpfile.c index 7ce0c6d648aa..4bde542b4f0c 100644 --- a/makedumpfile-1.6.2/makedumpfile.c +++ b/makedumpfile-1.6.2/makedumpfile.c @@ -1089,6 +1089,21 @@ fallback_to_current_page_size(void) return TRUE; } +static int populate_kernel_version(void) +{ + struct utsname utsname; + + if (uname(&utsname)) { + ERRMSG("Cannot get name and information about current kernel : %s\n", + strerror(errno)); + return FALSE; + } + + info->kernel_version = get_kernel_version(utsname.release); + + return TRUE; +} + int check_release(void) { @@ -1120,11 +1135,8 @@ check_release(void) } } - info->kernel_version = get_kernel_version(info->system_utsname.release); - if (info->kernel_version == FALSE) { - ERRMSG("Can't get the kernel version.\n"); + if (!populate_kernel_version()) return FALSE; - } return TRUE; } @@ -10973,20 +10985,14 @@ int is_crashkernel_mem_reserved(void) static int get_page_offset(void) { - struct utsname utsname; - if (uname(&utsname)) { - ERRMSG("Cannot get name and information about current kernel : %s", - strerror(errno)); + if (!populate_kernel_version()) return FALSE; - } - info->kernel_version = get_kernel_version(utsname.release); get_versiondep_info(); return TRUE; } - /* Returns the physical address of start of crash notes buffer for a kernel. */ static int get_sys_kernel_vmcoreinfo(uint64_t *addr, uint64_t *len) { @@ -11363,6 +11369,9 @@ main(int argc, char *argv[]) MSG("Try `makedumpfile --help' for more information.\n"); goto out; } + if (!populate_kernel_version()) + goto out; + if (info->kernel_version < KERNEL_VERSION(4, 11, 0) && !info->flag_force) { MSG("mem-usage not supported for this kernel.\n"); -- 2.7.4