Commit fb75437b authored by Krzysztof Kozlowski's avatar Krzysztof Kozlowski Committed by Will Deacon
Browse files

arm_mpam: Force __iomem casts 



Code allocates standard kernel memory to pass to the MPAM, which expects
__iomem.  The code is safe, because __iomem accessors should work fine
on kernel mapped memory, however leads to sparse warnings:

  test_mpam_devices.c:327:42: warning: incorrect type in initializer (different address spaces)
  test_mpam_devices.c:327:42:    expected char [noderef] __iomem *buf
  test_mpam_devices.c:327:42:    got void *
  test_mpam_devices.c:342:24: warning: cast removes address space '__iomem' of expression

Cast the pointer to memory via __force to silence them.

Signed-off-by: default avatarKrzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Reported-by: default avatarkernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202512160133.eAzPdJv2-lkp@intel.com/


Acked-by: default avatarBen Horgan <ben.horgan@arm.com>
Signed-off-by: default avatarJames Morse <james.morse@arm.com>
Signed-off-by: default avatarWill Deacon <will@kernel.org>
parent c1376f1f

drivers/resctrl/test_mpam_devices.c

+2 −2
Original line number Diff line number Diff line
@@ -332,7 +332,7 @@ static void __test_mpam_reset_msc_bitmap(struct mpam_msc *msc, u16 reg, u16 wd) 


static void test_mpam_reset_msc_bitmap(struct kunit *test)

{

	char __iomem *buf = kunit_kzalloc(test, SZ_16K, GFP_KERNEL);

	char __iomem *buf = (__force char __iomem *)kunit_kzalloc(test, SZ_16K, GFP_KERNEL);

	struct mpam_msc fake_msc = {};

	u32 *test_result;
@@ -347,7 +347,7 @@ static void test_mpam_reset_msc_bitmap(struct kunit *test) 
	mutex_init(&fake_msc.part_sel_lock);

	mutex_lock(&fake_msc.part_sel_lock);



	test_result = (u32 *)(buf + MPAMCFG_CPBM);

	test_result = (__force u32 *)(buf + MPAMCFG_CPBM);



	__test_mpam_reset_msc_bitmap(&fake_msc, MPAMCFG_CPBM, 0);

	KUNIT_EXPECT_EQ(test, test_result[0], 0);