| Message ID | 20211123090641.3654006-1-calvinzhang.cool@gmail.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm: kmemleak: alloc gray object for reserved region with direct map. | expand |
On Tue, Nov 23, 2021 at 05:06:41PM +0800, Calvin Zhang wrote: > Reserved regions with direct mapping may contain references to other > regions. CMA region with fixed location is reserved without creating > kmemleak_object for it. > > So add them as gray kmemleak objects. Do you get any kmemleak false positives without this patch? It would be good to include them in the commit message. Without seeing a false positive caused by this, I'm not convinced it is the right approach. You mentioned CMA but telling kmemleak about the whole CMA region is a pretty big hammer. I'd rather add individual kmemleak_alloc_*() calls in cma_alloc().
On Thu, Nov 25, 2021 at 05:17:53PM +0000, Catalin Marinas wrote: >On Tue, Nov 23, 2021 at 05:06:41PM +0800, Calvin Zhang wrote: >> Reserved regions with direct mapping may contain references to other >> regions. CMA region with fixed location is reserved without creating >> kmemleak_object for it. >> >> So add them as gray kmemleak objects. > >Do you get any kmemleak false positives without this patch? It would be >good to include them in the commit message. Sorry, no. I thought it was possible before I saw this commit: 620951e27457 ("mm/cma: make kmemleak ignore CMA regions"). > >Without seeing a false positive caused by this, I'm not convinced it is >the right approach. You mentioned CMA but telling kmemleak about the >whole CMA region is a pretty big hammer. I'd rather add individual >kmemleak_alloc_*() calls in cma_alloc(). Yeah, I agree. -- Calvin
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index bdca35284ceb..116c582fea7a 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -26,6 +26,7 @@ #include <linux/serial_core.h> #include <linux/sysfs.h> #include <linux/random.h> +#include <linux/kmemleak.h> #include <asm/setup.h> /* for COMMAND_LINE_SIZE */ #include <asm/page.h> @@ -522,9 +523,12 @@ static int __init __reserved_mem_reserve_reg(unsigned long node, size = dt_mem_next_cell(dt_root_size_cells, &prop); if (size && - early_init_dt_reserve_memory_arch(base, size, nomap) == 0) + early_init_dt_reserve_memory_arch(base, size, nomap) == 0) { pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %lu MiB\n", uname, &base, (unsigned long)(size / SZ_1M)); + if (!nomap) + kmemleak_alloc_phys(base, size, 0, 0); + } else pr_info("Reserved memory: failed to reserve memory for node '%s': base %pa, size %lu MiB\n", uname, &base, (unsigned long)(size / SZ_1M));
Reserved regions with direct mapping may contain references to other regions. CMA region with fixed location is reserved without creating kmemleak_object for it. So add them as gray kmemleak objects. Signed-off-by: Calvin Zhang <calvinzhang.cool@gmail.com> --- drivers/of/fdt.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)