On 7/18/19 1:30 AM, Hans van Kranenburg wrote: > Hi, > > On 10/23/18 7:34 PM, Ian Jackson wrote: >> Control: retitle -1 max grant frames problem (domu freeze with >> linux-image-4.9.0-4-amd64) >> Control: severity -1 important >> Control: reassign -1 src:xen 4.8.3+xsa267+shim4.10.1+xsa267-1+deb9u9 > > my last comment in this bts bug was about: > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=29d11cfd8698038b87458ba4d1329b9da81150a5 > > ..which is in since linux 4.13-rc2, and buster has 4.19+ > > Is there anyone who would wants to try reproduce the max grant frames > problem on buster with Xen 4.11 and Linux 4.19 dom0/domU? > > The 'xen/grant-table: max_grant_frames reached' should show up on the > serial console. I'd like to see a test report of it actually happening.
I actually just did this, by putting max_grant_frames = 4 in a domU config file and starting it (Linux 4.19 domU on Xen 4.11): Welcome to Debian GNU/Linux 10 (buster)! [ 5.499058] systemd[1]: Set hostname to <debug-btrfs-buster>. [ 5.552968] xen:grant_table: xen/grant-table: max_grant_frames reached cur=4 extra=1 limit=4 gnttab_free_count=3 req_entries=1 [ 5.554012] xen:grant_table: xen/grant-table: max_grant_frames reached cur=4 extra=1 limit=4 gnttab_free_count=3 req_entries=1 [ 5.555858] xen:grant_table: xen/grant-table: max_grant_frames reached cur=4 extra=1 limit=4 gnttab_free_count=3 req_entries=1 [ 5.556950] xen:grant_table: xen/grant-table: max_grant_frames reached cur=4 extra=1 limit=4 gnttab_free_count=3 req_entries=1 [ 5.557082] xen:grant_table: xen/grant-table: max_grant_frames reached cur=4 extra=1 limit=4 gnttab_free_count=3 req_entries=1 [ 5.557295] xen:grant_table: xen/grant-table: max_grant_frames reached cur=4 extra=1 limit=4 gnttab_free_count=3 req_entries=1 [ 5.557636] xen:grant_table: xen/grant-table: max_grant_frames reached cur=4 extra=1 limit=4 gnttab_free_count=3 req_entries=1 [ 5.558960] xen:grant_table: xen/grant-table: max_grant_frames reached cur=4 extra=1 limit=4 gnttab_free_count=3 req_entries=1 [ 5.559800] xen:grant_table: xen/grant-table: max_grant_frames reached cur=4 extra=1 limit=4 gnttab_free_count=3 req_entries=1 [ 6.014291] gnttab_expand: 159 callbacks suppressed [ 6.014296] xen:grant_table: xen/grant-table: max_grant_frames reached cur=4 extra=1 limit=4 gnttab_free_count=0 req_entries=3 [ 6.014351] xen:grant_table: xen/grant-table: max_grant_frames reached cur=4 extra=1 limit=4 gnttab_free_count=0 req_entries=8 [ 6.033683] xen:grant_table: xen/grant-table: max_grant_frames reached cur=4 extra=1 limit=4 gnttab_free_count=0 req_entries=3 [ 6.055013] xen:grant_table: xen/grant-table: max_grant_frames reached cur=4 extra=1 limit=4 gnttab_free_count=0 req_entries=3 [ 6.055729] xen:grant_table: xen/grant-table: max_grant_frames reached cur=4 extra=1 limit=4 gnttab_free_count=0 req_entries=26 [ 6.060256] xen:grant_table: xen/grant-table: max_grant_frames reached cur=4 extra=1 limit=4 gnttab_free_count=0 req_entries=3 [ 6.077000] xen:grant_table: xen/grant-table: max_grant_frames reached cur=4 extra=1 limit=4 gnttab_free_count=0 req_entries=3 [ 6.109760] xen:grant_table: xen/grant-table: max_grant_frames reached cur=4 extra=1 limit=4 gnttab_free_count=0 req_entries=3 [ 6.138126] xen:grant_table: xen/grant-table: max_grant_frames reached cur=4 extra=1 limit=4 gnttab_free_count=0 req_entries=3 [ 6.148626] xen:grant_table: xen/grant-table: max_grant_frames reached cur=4 extra=1 limit=4 gnttab_free_count=0 req_entries=3 Yay. Better info for the users! Also, there's a patch in review that can improve the situation: https://lists.xenproject.org/archives/html/xen-devel/2019-11/msg01607.html The biggest annoyance in our Xen 4.11 now is that the default value for the hypervisor command line of gnttab_max_frames is raised to 64 from 32 a while ago, but the toolstack overwrites this again with a default of 32. The patch attempts to fix that. Hans
