diff options
author | Alexandru Elisei <alexandru.elisei@arm.com> | 2022-06-16 14:48:19 +0100 |
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committer | Will Deacon <will@kernel.org> | 2022-07-01 16:08:06 +0100 |
commit | 28b96259fbdf602178d209fe93a0eddd3eec07d8 (patch) | |
tree | 1cb4e7d0ab9f92a21e9c176ac4c597c500a96900 | |
parent | 9d655190e466fd6a0b042ba8107ec06570c2e6d5 (diff) | |
download | kvmtool-28b96259fbdf602178d209fe93a0eddd3eec07d8.tar.gz |
builtin-run: Rework RAM size validation
host_ram_size() uses sysconf() to calculate the available ram, and
sysconf() can fail. When that happens, host_ram_size() returns 0. kvmtool
warns the user when the configured VM ram size exceeds the size of the
host's memory, but doesn't take into account that host_ram_size() can
return 0. If the function returns zero, skip the warning.
Since this can only happen when the user sets the memory size (via the
-m/--mem command line argument), skip the check entirely if the user hasn't
set it. Move the check to kvm_run_validate_cfg(), as it checks for valid
user configuration.
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Reviewed-and-Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20220616134828.129006-4-alexandru.elisei@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
-rw-r--r-- | builtin-run.c | 20 |
1 files changed, 13 insertions, 7 deletions
diff --git a/builtin-run.c b/builtin-run.c index 2bf93fe1..e1770b3c 100644 --- a/builtin-run.c +++ b/builtin-run.c @@ -509,6 +509,8 @@ static void kvm_run_set_real_cmdline(struct kvm *kvm) static void kvm_run_validate_cfg(struct kvm *kvm) { + u64 available_ram; + if (kvm->cfg.kernel_filename && kvm->cfg.firmware_filename) die("Only one of --kernel or --firmware can be specified"); @@ -518,6 +520,17 @@ static void kvm_run_validate_cfg(struct kvm *kvm) if (kvm->cfg.firmware_filename && kvm->cfg.initrd_filename) pr_warning("Ignoring initrd file when loading a firmware image"); + + if (kvm->cfg.ram_size) { + /* User specifies RAM size in megabytes. */ + kvm->cfg.ram_size <<= MB_SHIFT; + available_ram = host_ram_size(); + if (available_ram && kvm->cfg.ram_size > available_ram) { + pr_warning("Guest memory size %lluMB exceeds host physical RAM size %lluMB", + (unsigned long long)kvm->cfg.ram_size >> MB_SHIFT, + (unsigned long long)available_ram >> MB_SHIFT); + } + } } static struct kvm *kvm_cmd_run_init(int argc, const char **argv) @@ -596,13 +609,6 @@ static struct kvm *kvm_cmd_run_init(int argc, const char **argv) if (!kvm->cfg.ram_size) kvm->cfg.ram_size = get_ram_size(kvm->cfg.nrcpus); - else - kvm->cfg.ram_size <<= MB_SHIFT; - - if (kvm->cfg.ram_size > host_ram_size()) - pr_warning("Guest memory size %lluMB exceeds host physical RAM size %lluMB", - (unsigned long long)kvm->cfg.ram_size >> MB_SHIFT, - (unsigned long long)host_ram_size() >> MB_SHIFT); if (!kvm->cfg.dev) kvm->cfg.dev = DEFAULT_KVM_DEV; |