[PATCH 5.19 044/158] net: ipa: dont assume SMEM is page-aligned

From: Greg Kroah-Hartman
Date: Mon Aug 29 2022 - 07:21:59 EST


From: Alex Elder <elder@xxxxxxxxxx>

[ Upstream commit b8d4380365c515d8e0351f2f46d371738dd19be1 ]

In ipa_smem_init(), a Qualcomm SMEM region is allocated (if needed)
and then its virtual address is fetched using qcom_smem_get(). The
physical address associated with that region is also fetched.

The physical address is adjusted so that it is page-aligned, and an
attempt is made to update the size of the region to compensate for
any non-zero adjustment.

But that adjustment isn't done properly. The physical address is
aligned twice, and as a result the size is never actually adjusted.

Fix this by *not* aligning the "addr" local variable, and instead
making the "phys" local variable be the adjusted "addr" value.

Fixes: a0036bb413d5b ("net: ipa: define SMEM memory region for IPA")
Signed-off-by: Alex Elder <elder@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220818134206.567618-1-elder@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ipa/ipa_mem.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ipa/ipa_mem.c b/drivers/net/ipa/ipa_mem.c
index 1e9eae208e44f..53a1dbeaffa6d 100644
--- a/drivers/net/ipa/ipa_mem.c
+++ b/drivers/net/ipa/ipa_mem.c
@@ -568,7 +568,7 @@ static int ipa_smem_init(struct ipa *ipa, u32 item, size_t size)
}

/* Align the address down and the size up to a page boundary */
- addr = qcom_smem_virt_to_phys(virt) & PAGE_MASK;
+ addr = qcom_smem_virt_to_phys(virt);
phys = addr & PAGE_MASK;
size = PAGE_ALIGN(size + addr - phys);
iova = phys; /* We just want a direct mapping */
--
2.35.1