current/SOURCES/net-ipa-don-t-assume-smem-is-page-aligned.patch

From 8d590e275cdf797c08acb58439f6911c403a853b Mon Sep 17 00:00:00 2001
From: Sasha Levin <sashal@kernel.org>
Date: Thu, 18 Aug 2022 08:42:05 -0500
Subject: net: ipa: don't assume SMEM is page-aligned

From: Alex Elder <elder@linaro.org>

[ 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@linaro.org>
Link: https://lore.kernel.org/r/20220818134206.567618-1-elder@linaro.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 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

1	From 8d590e275cdf797c08acb58439f6911c403a853b Mon Sep 17 00:00:00 2001
2	From: Sasha Levin <sashal@kernel.org>
3	Date: Thu, 18 Aug 2022 08:42:05 -0500
4	Subject: net: ipa: don't assume SMEM is page-aligned
5
6	From: Alex Elder <elder@linaro.org>
7
8	[ Upstream commit b8d4380365c515d8e0351f2f46d371738dd19be1 ]
9
10	In ipa_smem_init(), a Qualcomm SMEM region is allocated (if needed)
11	and then its virtual address is fetched using qcom_smem_get(). The
12	physical address associated with that region is also fetched.
13
14	The physical address is adjusted so that it is page-aligned, and an
15	attempt is made to update the size of the region to compensate for
16	any non-zero adjustment.
17
18	But that adjustment isn't done properly. The physical address is
19	aligned twice, and as a result the size is never actually adjusted.
20
21	Fix this by not aligning the "addr" local variable, and instead
22	making the "phys" local variable be the adjusted "addr" value.
23
24	Fixes: a0036bb413d5b ("net: ipa: define SMEM memory region for IPA")
25	Signed-off-by: Alex Elder <elder@linaro.org>
26	Link: https://lore.kernel.org/r/20220818134206.567618-1-elder@linaro.org
27	Signed-off-by: Jakub Kicinski <kuba@kernel.org>
28	Signed-off-by: Sasha Levin <sashal@kernel.org>
29	---
30	drivers/net/ipa/ipa_mem.c \| 2 +-
31	1 file changed, 1 insertion(+), 1 deletion(-)
32
33	diff --git a/drivers/net/ipa/ipa_mem.c b/drivers/net/ipa/ipa_mem.c
34	index 1e9eae208e44f..53a1dbeaffa6d 100644
35	--- a/drivers/net/ipa/ipa_mem.c
36	+++ b/drivers/net/ipa/ipa_mem.c
37	@@ -568,7 +568,7 @@ static int ipa_smem_init(struct ipa *ipa, u32 item, size_t size)
38	}
39
40	/* Align the address down and the size up to a page boundary */
41	- addr = qcom_smem_virt_to_phys(virt) & PAGE_MASK;
42	+ addr = qcom_smem_virt_to_phys(virt);
43	phys = addr & PAGE_MASK;
44	size = PAGE_ALIGN(size + addr - phys);
45	iova = phys; /* We just want a direct mapping */
46	--
47	2.35.1
48