Re: [Crash-utility] [PATCH] Fix for the "kmem -i" option on Linux 5.0

----- Original Message ----- > Fix for the "kmem -i" option on Linux 5.0 and later kernels that > contain commit ca79b0c211af63fa3276f0e3fd7dd9ada2439839, titled > "mm: convert totalram_pages and totalhigh_pages variables to atomic". > Without the patch, the command prints some incorrect values, and > besides doesn't print high/low memory information on kernels which > are configured with CONFIG_HIGHMEM. Hi Kazu, Thanks again -- the patch is queued for crash-7.2.6: https://github.com/crash-utility/crash/commit/942d813cda354a5f4234fd36e9c... Dave

> crash> kmem -i > PAGES TOTAL PERCENTAGE > TOTAL MEM -4395174638254716088 53602483503169.4 GB ---- > FREE 398314 1.5 GB 0% of TOTAL MEM > USED -4395174638255114402 53602483503167.9 GB 0% of TOTAL MEM > ... > > Tested with 5.0 and 4.20 Fedora kernels for x86_64 and x86. > > Signed-off-by: Kazuhito Hagio <k-hagio(a)ab.jp.nec.com&gt; > --- > memory.c | 75 +++++++++++++++++++++++++++----------------------------- > 1 file changed, 36 insertions(+), 39 deletions(-) > > diff --git a/memory.c b/memory.c > index 9c1019a..ab561b3 100644 > --- a/memory.c > +++ b/memory.c > @@ -910,26 +910,40 @@ vm_init(void) > if (IS_VMALLOC_ADDR(vt->mem_map)) > vt->flags |= V_MEM_MAP; > vt->total_pages = BTOP(VTOP(vt->high_memory)); > - switch (get_syment_array("totalram_pages", sp_array, 2)) > - { > - case 1: > - get_symbol_data("totalram_pages", sizeof(ulong), > - &vt->totalram_pages); > - break; > - case 2: > - if (!(readmem(sp_array[0]->value, KVADDR, > - &value1, sizeof(ulong), > - "totalram_pages #1", RETURN_ON_ERROR))) > + > + if (symbol_exists("_totalram_pages")) { > + readmem(symbol_value("_totalram_pages") + > + OFFSET(atomic_t_counter), KVADDR, > + &vt->totalram_pages, sizeof(ulong), > + "_totalram_pages", FAULT_ON_ERROR); > + } else { > + switch (get_syment_array("totalram_pages", sp_array, 2)) > + { > + case 1: > + get_symbol_data("totalram_pages", sizeof(ulong), > + &vt->totalram_pages); > break; > - if (!(readmem(sp_array[1]->value, KVADDR, > - &value2, sizeof(ulong), > - "totalram_pages #2", RETURN_ON_ERROR))) > - break; > - vt->totalram_pages = MAX(value1, value2); > - break; > + case 2: > + if (!(readmem(sp_array[0]->value, KVADDR, > + &value1, sizeof(ulong), > + "totalram_pages #1", RETURN_ON_ERROR))) > + break; > + if (!(readmem(sp_array[1]->value, KVADDR, > + &value2, sizeof(ulong), > + "totalram_pages #2", RETURN_ON_ERROR))) > + break; > + vt->totalram_pages = MAX(value1, value2); > + break; > + } > } > > - if (symbol_exists("totalhigh_pages")) { > + if (symbol_exists("_totalhigh_pages")) { > + readmem(symbol_value("_totalhigh_pages") + > + OFFSET(atomic_t_counter), KVADDR, > + &vt->totalhigh_pages, sizeof(ulong), > + "_totalhigh_pages", FAULT_ON_ERROR); > + vt->total_pages += vt->totalhigh_pages; > + } else if (symbol_exists("totalhigh_pages")) { > switch (get_syment_array("totalhigh_pages", sp_array, 2)) > { > case 1: > @@ -8169,7 +8183,6 @@ dump_kmeminfo(void) > long nr_file_pages, nr_slab; > ulong swapper_space_nrpages; > ulong pct; > - ulong value1, value2; > uint tmp; > struct meminfo meminfo; > struct gnu_request req; > @@ -8177,7 +8190,6 @@ dump_kmeminfo(void) > ulong get_totalram; > ulong get_buffers; > ulong get_slabs; > - struct syment *sp_array[2]; > char buf[BUFSIZE]; > > > @@ -8210,7 +8222,8 @@ dump_kmeminfo(void) > * Prior to 2.3.36, count all mem_map pages minus the reserved > ones. > * From 2.3.36 onwards, use "totalram_pages" if set. > */ > - if (symbol_exists("totalram_pages")) { > + if (symbol_exists("totalram_pages") || > + symbol_exists("_totalram_pages")) { > totalram_pages = vt->totalram_pages ? > vt->totalram_pages : get_totalram; > } else > @@ -8362,25 +8375,9 @@ dump_kmeminfo(void) > fprintf(fp, "%13s %7ld %11s %3ld%% of TOTAL MEM\n", > "SLAB", get_slabs, pages_to_size(get_slabs, buf), pct); > > - if (symbol_exists("totalhigh_pages")) { > - switch (get_syment_array("totalhigh_pages", sp_array, 2)) > - { > - case 1: > - get_symbol_data("totalhigh_pages", sizeof(ulong), > - &totalhigh_pages); > - break; > - case 2: > - if (!(readmem(sp_array[0]->value, KVADDR, > - &value1, sizeof(ulong), > - "totalhigh_pages #1", RETURN_ON_ERROR))) > - break; > - if (!(readmem(sp_array[1]->value, KVADDR, > - &value2, sizeof(ulong), > - "totalhigh_pages #2", RETURN_ON_ERROR))) > - break; > - totalhigh_pages = MAX(value1, value2); > - break; > - } > + if (symbol_exists("totalhigh_pages") || > + symbol_exists("_totalhigh_pages")) { > + totalhigh_pages = vt->totalhigh_pages; > > pct = totalhigh_pages ? > (totalhigh_pages * 100)/totalram_pages : 0; > -- > 2.17.0 > > -- > Crash-utility mailing list > Crash-utility(a)redhat.com > https://www.redhat.com/mailman/listinfo/crash-utility > -- Crash-utility mailing list Crash-utility(a)redhat.com https://www.redhat.com/mailman/listinfo/crash-utility