| Message ID | 1240a14dea2f75d2e5b8d8e8bb685fac956629c6.1722442563.git.matthew.barnes@cloud.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [XEN,v7] tools/lsevtchn: Use errno macro to handle hypercall error cases | expand |
On Wed, Jul 31, 2024 at 05:18:44PM +0100, Matthew Barnes wrote: > Currently, lsevtchn aborts its event channel enumeration when it hits > an event channel that is owned by Xen. > > lsevtchn does not distinguish between different hypercall errors, which > results in lsevtchn missing potential relevant event channels with > higher port numbers. > > Use the errno macro to distinguish between hypercall errors, and > continue event channel enumeration if the hypercall error is not > critical to enumeration. > > Signed-off-by: Matthew Barnes <matthew.barnes@cloud.com> Reviewed-by: Anthony PERARD <anthony.perard@vates.tech> Thanks,
diff --git a/tools/xcutils/lsevtchn.c b/tools/xcutils/lsevtchn.c index d1710613ddc5..30c8d847b814 100644 --- a/tools/xcutils/lsevtchn.c +++ b/tools/xcutils/lsevtchn.c @@ -3,6 +3,7 @@ #include <stdint.h> #include <string.h> #include <stdio.h> +#include <errno.h> #include <xenctrl.h> @@ -24,7 +25,23 @@ int main(int argc, char **argv) status.port = port; rc = xc_evtchn_status(xch, &status); if ( rc < 0 ) - break; + { + switch ( errno ) + { + case EACCES: /* Xen-owned evtchn */ + continue; + + case EINVAL: /* Port enumeration has ended */ + rc = 0; + break; + + default: + perror("xc_evtchn_status"); + rc = 1; + break; + } + goto out; + } if ( status.status == EVTCHNSTAT_closed ) continue; @@ -58,7 +75,8 @@ int main(int argc, char **argv) printf("\n"); } + out: xc_interface_close(xch); - return 0; + return rc; }
Currently, lsevtchn aborts its event channel enumeration when it hits an event channel that is owned by Xen. lsevtchn does not distinguish between different hypercall errors, which results in lsevtchn missing potential relevant event channels with higher port numbers. Use the errno macro to distinguish between hypercall errors, and continue event channel enumeration if the hypercall error is not critical to enumeration. Signed-off-by: Matthew Barnes <matthew.barnes@cloud.com> --- Changes in v7: - All error paths return error code 1 from lsevtchn - Simplify perror message to failing function "xc_evtchn_status" Changes in v6: - Add blank space before label Changes in v5: - Code style changes to switch statement Changes in v4: - Catch non-critical errors and fail on everything else, instead of catching few known critical errors and ignoring everything else - Use 'perror' to describe miscellaneous critical errors - Return appropriate error code from lsevtchn tool - Tweak commit description --- tools/xcutils/lsevtchn.c | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-)