----- Original Message ----- ... > > > > As far as the gcore extension module, that is maintained by Daisuke Hatayama, > > and he make all decisions w/respect to that codebase. I've cc'd this response > > to him. > > Thanks Zhao for your patch set. > Thanks for ccing me, Dave. > > I agree that ZRAM support is useful as your explanation. On the other > hand, it is not only for crash gcore command, but also for crash utility. I think > it more natural than the current implementation of your patch set that you > implement a ZRAM support in crash utility and then do it in crash gcore command. > > If the ZRAM support were transparent to readmem() interface, there would be no need > to implement crash gcore command at all. If not, there would be need to add a new code > for the ZRAM support just corresponding to the following stanza in > 0001-gcore-add-support-zram-swap.patch: > > @@ -225,6 +417,18 @@ void gcore_coredump(void) > strerror(errno)); > } else { > pagefaultf("page fault at %lx\n", addr); > + if (paddr != 0) { > + pte_val = paddr; > + if(try_zram_decompress(pte_val, (unsigned char *)buffer) == PAGE_SIZE) > + { > + error(WARNING, "zram decompress successed\n"); > + if (fwrite(buffer, PAGE_SIZE, 1, gcore->fp) != 1) > + error(FATAL, "%s: write: %s\n", gcore->corename, strerror(errno)); > + continue; > + } > + > + } I'm not clear on how zram is linked into the user-space mapping. For user space that has been swapped out to a zram swap device, I presume it's the same as is, but it references the zram swap device. But for other user-space mappings (non-swapped), what does the "vm -p" display for user space virtual address pages that are backed by zram? And for that matter, what does "vtop <address>" show? Thanks, Dave -- Crash-utility mailing list Crash-utility@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/crash-utility