2022-08-18 14:08:38

by Alex Elder

[permalink] [raw]
Subject: [PATCH net] net: ipa: don't assume SMEM is page-aligned

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 <[email protected]>
---
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 */
--
2.34.1


2022-08-23 02:17:31

by patchwork-bot+netdevbpf

[permalink] [raw]
Subject: Re: [PATCH net] net: ipa: don't assume SMEM is page-aligned

Hello:

This patch was applied to netdev/net.git (master)
by Jakub Kicinski <[email protected]>:

On Thu, 18 Aug 2022 08:42:05 -0500 you wrote:
> 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.
>
> [...]

Here is the summary with links:
- [net] net: ipa: don't assume SMEM is page-aligned
https://git.kernel.org/netdev/net/c/b8d4380365c5

You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html