From: Qian Cai cai@gmx.us
No matching commit upstream, but the issue being addressed no longer exists after commit 80424b02d42b ("efi: Reduce the amount of memblock reservations for persistent allocations") was merged for the 5.0 cycle.
unreferenced object 0xffff8096c1acf580 (size 128): comm "swapper/63", pid 0, jiffies 4294937418 (age 1201.230s) hex dump (first 32 bytes): 80 87 b5 c1 96 00 00 00 00 00 cc c2 16 00 00 00 ................ 00 00 01 00 00 00 00 00 6b 6b 6b 6b 6b 6b 6b 6b ........kkkkkkkk backtrace: [<000000001d2549ba>] kmem_cache_alloc_trace+0x430/0x500 [<0000000093a6dfab>] efi_mem_reserve_persistent+0x50/0xf8 [<000000000a730828>] its_cpu_init_lpis+0x394/0x4b8 [<00000000edf04e07>] its_cpu_init+0x104/0x150 [<000000004d0342c5>] gic_starting_cpu+0x34/0x40 [<000000005d9da772>] cpuhp_invoke_callback+0x228/0x1d68 [<0000000061eace9b>] notify_cpu_starting+0xc0/0x118 [<0000000048bc2dc5>] secondary_start_kernel+0x23c/0x3b0 [<0000000015137d6a>] 0xffffffffffffffff
efi_mem_reserve_persistent+0x50/0xf8: kmalloc at include/linux/slab.h:546 (inlined by) efi_mem_reserve_persistent at drivers/firmware/efi/efi.c:979
This line,
rsv = kmalloc(sizeof(*rsv), GFP_ATOMIC);
Kmemleak has a known limitation that can only track pointers in the kernel virtual space. Hence, it will report false positives due to "rsv" will only reference to other physical addresses,
rsv->next = efi_memreserve_root->next; efi_memreserve_root->next = __pa(rsv);
Fixes: a23d3bb05ccb ("efi: add API to reserve memory persistently across ...") Cc: stable@vger.kernel.org # v4.20 Cc: Ingo Molnar mingo@kernel.org Cc: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Qian Cai cai@gmx.us Signed-off-by: Ard Biesheuvel ard.biesheuvel@linaro.org --- drivers/firmware/efi/efi.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 415849bab233..7fcfe8a7ae98 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -31,6 +31,7 @@ #include <linux/acpi.h> #include <linux/ucs2_string.h> #include <linux/memblock.h> +#include <linux/kmemleak.h>
#include <asm/early_ioremap.h>
@@ -1000,6 +1001,8 @@ int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) if (!rsv) return -ENOMEM;
+ kmemleak_ignore(rsv); + rsv->base = addr; rsv->size = size;