[Xen-devel] [PATCH v1] libxl: remove limit for default number of event channels

[Olaf Hering <olaf@aepfle.de>]

The imposed limit of 1023 is too low for a three digit value of vcpus.
Remove the arbitrary value of 1023 and let Xen decide about the upper limit.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
---
 docs/man/xl.cfg.5.pod.in   | 8 +++-----
 tools/libxl/libxl_create.c | 2 +-
 2 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/docs/man/xl.cfg.5.pod.in b/docs/man/xl.cfg.5.pod.in
index 0e9e58a41a..ac3fe5f35a 100644
--- a/docs/man/xl.cfg.5.pod.in
+++ b/docs/man/xl.cfg.5.pod.in
@@ -1332,11 +1332,9 @@ L</vuart="uart"> to know how to enable vuart console.
 Limit the guest to using at most N event channels (PV interrupts).
 Guests use hypervisor resources for each event channel they use.
 
-The default of 1023 should be sufficient for typical guests.  The
-maximum value depends on what the guest supports.  Guests supporting the
-FIFO-based event channel ABI support up to 131,071 event channels.
-Other guests are limited to 4095 (64-bit x86 and ARM) or 1023 (32-bit
-x86).
+The maximum value depends on what the guest supports.  Guests supporting the
+FIFO-based event channel ABI support up to 131,071 event channels.  Other
+guests are limited to 4095 (64-bit x86 and ARM) or 1023 (32-bit x86).
 
 =item B<vdispl=[ "VDISPL_SPEC_STRING", "VDISPL_SPEC_STRING", ...]>
 
diff --git a/tools/libxl/libxl_create.c b/tools/libxl/libxl_create.c
index e7cb2dbc2b..17c128bc07 100644
--- a/tools/libxl/libxl_create.c
+++ b/tools/libxl/libxl_create.c
@@ -226,7 +226,7 @@ int libxl__domain_build_info_setdefault(libxl__gc *gc,
             b_info->iomem[i].gfn = b_info->iomem[i].start;
 
     if (!b_info->event_channels)
-        b_info->event_channels = 1023;
+        b_info->event_channels = -1U;
 
     libxl__arch_domain_build_info_setdefault(gc, b_info);
     libxl_defbool_setdefault(&b_info->dm_restrict, false);