Re: [PATCH v4 06/17] scs: add accounting

Marc Zyngier
2019-11-04T13:14:04Z

On 2019-11-01 23:21, Sami Tolvanen wrote:
> This change adds accounting for the memory allocated for shadow
> stacks.
>
> Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
> Reviewed-by: Kees Cook <keescook@chromium.org>
> ---
> drivers/base/node.c | 6 ++++++
> fs/proc/meminfo.c | 4 ++++
> include/linux/mmzone.h | 3 +++
> kernel/scs.c | 19 +++++++++++++++++++
> mm/page_alloc.c | 6 ++++++
> mm/vmstat.c | 3 +++
> 6 files changed, 41 insertions(+)
>
> diff --git a/drivers/base/node.c b/drivers/base/node.c
> index 296546ffed6c..111e58ec231e 100644
> --- a/drivers/base/node.c
> +++ b/drivers/base/node.c
> @@ -415,6 +415,9 @@ static ssize_t node_read_meminfo(struct device
> *dev,
> "Node %d AnonPages: %8lu kB\n"
> "Node %d Shmem: %8lu kB\n"
> "Node %d KernelStack: %8lu kB\n"
> +#ifdef CONFIG_SHADOW_CALL_STACK
> + "Node %d ShadowCallStack:%8lu kB\n"
> +#endif
> "Node %d PageTables: %8lu kB\n"
> "Node %d NFS_Unstable: %8lu kB\n"
> "Node %d Bounce: %8lu kB\n"
> @@ -438,6 +441,9 @@ static ssize_t node_read_meminfo(struct device
> *dev,
> nid, K(node_page_state(pgdat, NR_ANON_MAPPED)),
> nid, K(i.sharedram),
> nid, sum_zone_node_page_state(nid, NR_KERNEL_STACK_KB),
> +#ifdef CONFIG_SHADOW_CALL_STACK
> + nid, sum_zone_node_page_state(nid, NR_KERNEL_SCS_BYTES) /
> 1024,
> +#endif
> nid, K(sum_zone_node_page_state(nid, NR_PAGETABLE)),
> nid, K(node_page_state(pgdat, NR_UNSTABLE_NFS)),
> nid, K(sum_zone_node_page_state(nid, NR_BOUNCE)),
> diff --git a/fs/proc/meminfo.c b/fs/proc/meminfo.c
> index 8c1f1bb1a5ce..49768005a79e 100644
> --- a/fs/proc/meminfo.c
> +++ b/fs/proc/meminfo.c
> @@ -103,6 +103,10 @@ static int meminfo_proc_show(struct seq_file *m,
> void *v)
> show_val_kb(m, "SUnreclaim: ", sunreclaim);
> seq_printf(m, "KernelStack: %8lu kB\n",
> global_zone_page_state(NR_KERNEL_STACK_KB));
> +#ifdef CONFIG_SHADOW_CALL_STACK
> + seq_printf(m, "ShadowCallStack:%8lu kB\n",
> + global_zone_page_state(NR_KERNEL_SCS_BYTES) / 1024);
> +#endif
> show_val_kb(m, "PageTables: ",
> global_zone_page_state(NR_PAGETABLE));
>
> diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
> index bda20282746b..fcb8c1708f9e 100644
> --- a/include/linux/mmzone.h
> +++ b/include/linux/mmzone.h
> @@ -200,6 +200,9 @@ enum zone_stat_item {
> NR_MLOCK, /* mlock()ed pages found and moved off LRU */
> NR_PAGETABLE, /* used for pagetables */
> NR_KERNEL_STACK_KB, /* measured in KiB */
> +#if IS_ENABLED(CONFIG_SHADOW_CALL_STACK)

Is there any reason why you're not consistently using only one of
"#if IS_ENABLED(...)" or "#ifdef ...", but instead a mix of both?

Thanks,

M.
--
Jazz is not dead. It just smells funny...