linux-kernel - [PATCH AUTOSEL 5.4 007/175] media: staging: imgu: do not hold spinlock during freeing mmu page table

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20200608231848.3366970-7-sashal@kernel.org>
Date:   Mon,  8 Jun 2020 19:16:00 -0400
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     Bingbu Cao <bingbu.cao@...el.com>,
        Tomasz Figa <tfiga@...omium.org>,
        Sakari Ailus <sakari.ailus@...ux.intel.com>,
        Mauro Carvalho Chehab <mchehab+huawei@...nel.org>,
        Sasha Levin <sashal@...nel.org>, linux-media@...r.kernel.org,
        devel@...verdev.osuosl.org
Subject: [PATCH AUTOSEL 5.4 007/175] media: staging: imgu: do not hold spinlock during freeing mmu page table

From: Bingbu Cao <bingbu.cao@...el.com>

[ Upstream commit e1ebe9f9c88e5a78fcc4670a9063c9b3cd87dda4 ]

ImgU need set the mmu page table in memory as uncached, and set back
to write-back when free the page table by set_memory_wb(),
set_memory_wb() can not do flushing without interrupt, so the spinlock
should not be hold during ImgU page alloc and free, the interrupt
should be enabled during memory cache flush.

This patch release spinlock before freeing pages table.

Signed-off-by: Bingbu Cao <bingbu.cao@...el.com>
Reviewed-by: Tomasz Figa <tfiga@...omium.org>
Signed-off-by: Sakari Ailus <sakari.ailus@...ux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@...nel.org>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/staging/media/ipu3/ipu3-mmu.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/staging/media/ipu3/ipu3-mmu.c b/drivers/staging/media/ipu3/ipu3-mmu.c
index 3d969b0522ab..abcf1f3e5f63 100644
--- a/drivers/staging/media/ipu3/ipu3-mmu.c
+++ b/drivers/staging/media/ipu3/ipu3-mmu.c
@@ -174,8 +174,10 @@ static u32 *imgu_mmu_get_l2pt(struct imgu_mmu *mmu, u32 l1pt_idx)
 	spin_lock_irqsave(&mmu->lock, flags);
 
 	l2pt = mmu->l2pts[l1pt_idx];
-	if (l2pt)
-		goto done;
+	if (l2pt) {
+		spin_unlock_irqrestore(&mmu->lock, flags);
+		return l2pt;
+	}
 
 	spin_unlock_irqrestore(&mmu->lock, flags);
 
@@ -190,8 +192,9 @@ static u32 *imgu_mmu_get_l2pt(struct imgu_mmu *mmu, u32 l1pt_idx)
 
 	l2pt = mmu->l2pts[l1pt_idx];
 	if (l2pt) {
+		spin_unlock_irqrestore(&mmu->lock, flags);
 		imgu_mmu_free_page_table(new_l2pt);
-		goto done;
+		return l2pt;
 	}
 
 	l2pt = new_l2pt;
@@ -200,7 +203,6 @@ static u32 *imgu_mmu_get_l2pt(struct imgu_mmu *mmu, u32 l1pt_idx)
 	pteval = IPU3_ADDR2PTE(virt_to_phys(new_l2pt));
 	mmu->l1pt[l1pt_idx] = pteval;
 
-done:
 	spin_unlock_irqrestore(&mmu->lock, flags);
 	return l2pt;
 }
-- 
2.25.1