From 55d62b8d4636e22290e1d93704ab0b85a8c1a860 Mon Sep 17 00:00:00 2001 From: Michal Orzel Date: Wed, 12 Mar 2025 11:16:19 +0100 Subject: [PATCH] tools/arm: Reject configuration with incorrect nr_spis value If the calculated value for nr_spis by the toolstack is bigger than the value provided by the user, we silently ignore the latter. This is not consistent with the approach we have in Xen on Arm when we try to reject incorrect configuration. Also, the documentation for nr_spis is incorrect as it mentions 991 as the number of max SPIs, where it should be 960 i.e. (1020 - 32) rounded down to the nearest multiple of 32. Signed-off-by: Michal Orzel Reviewed-by: Bertrand Marquis --- docs/man/xl.cfg.5.pod.in | 13 +++++-------- tools/libs/light/libxl_arm.c | 6 ++++++ 2 files changed, 11 insertions(+), 8 deletions(-) diff --git a/docs/man/xl.cfg.5.pod.in b/docs/man/xl.cfg.5.pod.in index 8e1422104e..7339c44efd 100644 --- a/docs/man/xl.cfg.5.pod.in +++ b/docs/man/xl.cfg.5.pod.in @@ -3083,14 +3083,11 @@ interval of colors (such as "0-4"). =item B An optional integer parameter specifying the number of SPIs (Shared -Peripheral Interrupts) to allocate for the domain. Max is 991 SPIs. If -the value specified by the `nr_spis` parameter is smaller than the -number of SPIs calculated by the toolstack based on the devices -allocated for the domain, or the `nr_spis` parameter is not specified, -the value calculated by the toolstack will be used for the domain. -Otherwise, the value specified by the `nr_spis` parameter will be used. -The number of SPIs should match the highest interrupt ID that will be -assigned to the domain. +Peripheral Interrupts) to allocate for the domain. Max is 960 SPIs. If +the `nr_spis` parameter is not specified, the value calculated by the toolstack +will be used for the domain. Otherwise, the value specified by the `nr_spis` +parameter will be used. The number of SPIs should match the highest interrupt +ID that will be assigned to the domain. =back diff --git a/tools/libs/light/libxl_arm.c b/tools/libs/light/libxl_arm.c index 5a9db5e85f..2d895408ca 100644 --- a/tools/libs/light/libxl_arm.c +++ b/tools/libs/light/libxl_arm.c @@ -181,6 +181,12 @@ int libxl__arch_domain_prepare_config(libxl__gc *gc, LOG(DEBUG, "Configure the domain"); + if (nr_spis > d_config->b_info.arch_arm.nr_spis) { + LOG(ERROR, "Provided nr_spis value is too small (minimum required %u)\n", + nr_spis); + return ERROR_FAIL; + } + config->arch.nr_spis = max(nr_spis, d_config->b_info.arch_arm.nr_spis); LOG(DEBUG, " - Allocate %u SPIs", config->arch.nr_spis);