[Crash-utility] Re: [PATCH v7 01/15] Fix the regression of cpumask_t for xen hyper

Hi Aditya, On Thu, Sep 5, 2024 at 7:49 PM Aditya Gupta <adityag(a)linux.ibm.com&gt; wrote: > > Hi Tao, > > On 05/09/24 03:40, Tao Liu wrote: > > Hi Aditya, > > > > On Wed, Sep 4, 2024 at 10:27 PM Aditya Gupta <adityag(a)linux.ibm.com&gt; wrote: > >> Hi Tao, > >> > >> Is this a separate independent patch or related to this series ? > >> > > This is an independent patch, but discovered when doing a regression > > test against the stack unwinding patchset. Since we have done the > > cpumask_t modification in [PATCH v6 10/14], the modification will > > continue in v7 as well. So I posted it with v7 together. > > > > Lianbo suggested that I separate some "less strongly connected with > > stack unwinding" patches from v7, which formed the part 1 as mentioned > > in [1]. Part 1 can be merged prior to the rest of part 2 & 3. So I > > think part 1 is also suitable for the cpumask_t regression patch. > > Yes, I agree. We can move 'Fix gdb_interface' patch also as independent. > It originally was required for the patch series to work, since 'info > threads' used to break, but now that can go independently. > Thanks for your suggestion. Yes, the 'Fix gdb_interface' patch is already in part 1 which can be merged prior. Let's wait for Lianbo's comments for this. Thanks, Tao Liu > > Thanks, > > Aditya Gupta > > > [1]: https://www.mail-archive.com/devel@lists.crash-utility.osci.io/msg01079.html > > > > Thanks, > > Tao Liu > > > >> - Aditya Gupta > >> > >> > >> On 04/09/24 13:19, Tao Liu wrote: > >>> There is a regression been found for xen hyper due to the commit: > >>> f615f8fab7bf ("Fix "irq -a" exceeding the memory range issue"). > >>> > >>> The reason is for xen hyper, kt->cpu is not initialized due to > >>> kernel_init() won't be called. So 0 would be assigned to cpulen and > >>> fails the GETBUF(). > >>> > >>> Before: > >>> crash> bt -c 2 > >>> bt: zero-size memory allocation! (called from 51f168) > >>> > >>> After: > >>> crash> bt -c 2 > >>> PCPU: 0 VCPU: ffff8300001b8080 > >>> #0 [ffff8300001bfe00] machine_crash_kexec at ffff83000010de72 > >>> #1 [ffff8300001bfe10] do_kexec_op at ffff83000010e3cb > >>> #2 [ffff8300001bfe50] do_console_io at ffff83000011aff4 > >>> #3 [ffff8300001bfe90] mod_l1_entry at ffff830000129045 > >>> #4 [ffff8300001bfea0] toggle_guest_mode at ffff8300001641bf > >>> #5 [ffff8300001bfeb0] do_iret at ffff830000164888 > >>> #6 [ffff8300001bff20] syscall_enter at ffff8300001633d2 > >>> > >>> Since xen hyper will initialize its own cpumask_t, this patch will reuse > >>> it for XEN_HYPER_MODE. In addition, this patch won't modify the similar > >>> code hunk in generic_get_irq_affinity(), because for xen, there is no > >>> "irq" cmd, so the regression won't be triggered. > >>> > >>> Cc: Sourabh Jain <sourabhjain(a)linux.ibm.com&gt; > >>> Cc: Hari Bathini <hbathini(a)linux.ibm.com&gt; > >>> Cc: Mahesh J Salgaonkar <mahesh(a)linux.ibm.com&gt; > >>> Cc: Naveen N. Rao <naveen.n.rao(a)linux.vnet.ibm.com&gt; > >>> Cc: Lianbo Jiang <lijiang(a)redhat.com&gt; > >>> Cc: HAGIO KAZUHITO(萩尾 一仁) <k-hagio-ab(a)nec.com&gt; > >>> Cc: Tao Liu <ltao(a)redhat.com&gt; > >>> Cc: Alexey Makhalov <alexey.makhalov(a)broadcom.com&gt; > >>> Cc: Aditya Gupta <adityag(a)linux.ibm.com&gt; > >>> Signed-off-by: Tao Liu <ltao(a)redhat.com&gt; > >>> --- > >>> tools.c | 6 ++++++ > >>> 1 file changed, 6 insertions(+) > >>> > >>> diff --git a/tools.c b/tools.c > >>> index 2b78b95..dec6e5b 100644 > >>> --- a/tools.c > >>> +++ b/tools.c > >>> @@ -16,6 +16,7 @@ > >>> */ > >>> > >>> #include "defs.h" > >>> +#include "xen_hyper_defs.h" > >>> #include <ctype.h> > >>> > >>> #ifdef VALGRIND > >>> @@ -6720,6 +6721,11 @@ get_cpumask_buf(void) > >>> { > >>> int cpulen, len_cpumask; > >>> > >>> +#ifdef XEN_HYPERVISOR_ARCH > >>> + if (XEN_HYPER_MODE() && XEN_HYPER_VALID_SIZE(cpumask_t)) > >>> + return (ulong *)GETBUF(XEN_HYPER_SIZE(cpumask_t)); > >>> +#endif > >>> + > >>> cpulen = DIV_ROUND_UP(kt->cpus, BITS_PER_LONG) * sizeof(ulong); > >>> len_cpumask = STRUCT_SIZE("cpumask_t"); > >>> if (len_cpumask > 0) >