[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[XEN v3 8/9] xen/arm: Restrict zeroeth_table_offset for ARM_64


  • To: <xen-devel@xxxxxxxxxxxxxxxxxxxx>
  • From: Ayan Kumar Halder <ayan.kumar.halder@xxxxxxx>
  • Date: Wed, 8 Feb 2023 12:05:28 +0000
  • Arc-authentication-results: i=1; mx.microsoft.com 1; spf=pass (sender ip is 165.204.84.17) smtp.rcpttodomain=lists.xenproject.org smtp.mailfrom=amd.com; dmarc=pass (p=quarantine sp=quarantine pct=100) action=none header.from=amd.com; dkim=none (message not signed); arc=none
  • Arc-message-signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=c7Yzg+nNX8nU4svwG9G763956tzSeXgDroKQZsR7IaM=; b=O81tc0a4pMeLGWa3YV89ZrO6Ut1aVcexYyAHZVOBLUid2dh9idKUpX/H5zJnxpLanyswSKSp/qcNHbkPQfM0yx7BQXZm5cPkWaKIkx+7Wp6QKfmOoQRZkwe/BswEhXRQ0pofkxsclBsW+hfWD0aug52zdUyGkGrKX3U9fOxXHWvOdnUHU80ZMO9ICbViRyMVtqKtPp8P0Rhut/lLAza+KKtuzDOwCuKzb7ZC9MJenqWHvYaEMy+qBfI42/O5aHpBHvGEEfwcEetGJskakokO71YQueeGu4qUWj+DieDvv1NxzV9ZJobVfGvkxYER/C6WzMFu291IugUCYP1PkMQDRw==
  • Arc-seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=VcoBNrkCfME6utYB3/h5MFkU5pCEihv5tvxvsDn4P8z/EHI0SdPKHa+kUCFOXAw9I7Mm/HgPdysWRJNBYJwfO3qZMfkQ1HMjd/22vPD+kqOBYShXYhVHIaNqxAsreyWXpXX8ugSMDi8nc3/v+2qWY1W70XEN52P7mRNTkiHKDBHKyvDjASCYqmzhfaAR12cQ+XZL/0D1SLf58qtgQX+z6ukGX6hKYVHQis4RbV2ToPfPNex0l3EQHE6NcxPwmp3aH4BUyvSGSuYx5uWYRQmrQyP4zqf2cjes13PeQnr2fqsgjGpqRsyv4lGdVRQbpnaLMgV5qgCmqkTHTM08D0Eanw==
  • Cc: <sstabellini@xxxxxxxxxx>, <stefano.stabellini@xxxxxxx>, <julien@xxxxxxx>, <Volodymyr_Babchuk@xxxxxxxx>, <bertrand.marquis@xxxxxxx>, <andrew.cooper3@xxxxxxxxxx>, <george.dunlap@xxxxxxxxxx>, <jbeulich@xxxxxxxx>, <wl@xxxxxxx>, <rahul.singh@xxxxxxx>, Ayan Kumar Halder <ayan.kumar.halder@xxxxxxx>
  • Delivery-date: Wed, 08 Feb 2023 12:06:31 +0000
  • List-id: Xen developer discussion <xen-devel.lists.xenproject.org>

When 32 bit physical addresses are used (ie ARM_PA_32=y),
"va >> ZEROETH_SHIFT" causes an overflow.
Also, there is no zeroeth level page table on Arm 32-bit.

Also took the opportunity to clean up dump_pt_walk(). One could use
DECLARE_OFFSETS() macro instead of declaring the declaring an array
of page table offsets.

Signed-off-by: Ayan Kumar Halder <ayan.kumar.halder@xxxxxxx>
---
Changes from -

v1 - Removed the duplicate declaration for DECLARE_OFFSETS.

v2 - 1. Reworded the commit message. 
2. Use CONFIG_ARM_PA_32 to restrict zeroeth_table_offset.

 xen/arch/arm/include/asm/lpae.h | 4 ++++
 xen/arch/arm/mm.c               | 7 +------
 2 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/xen/arch/arm/include/asm/lpae.h b/xen/arch/arm/include/asm/lpae.h
index 3fdd5d0de2..998edeed6e 100644
--- a/xen/arch/arm/include/asm/lpae.h
+++ b/xen/arch/arm/include/asm/lpae.h
@@ -259,7 +259,11 @@ lpae_t mfn_to_xen_entry(mfn_t mfn, unsigned int attr);
 #define first_table_offset(va)  TABLE_OFFSET(first_linear_offset(va))
 #define second_table_offset(va) TABLE_OFFSET(second_linear_offset(va))
 #define third_table_offset(va)  TABLE_OFFSET(third_linear_offset(va))
+#ifdef CONFIG_ARM_PA_32
+#define zeroeth_table_offset(va)  0
+#else
 #define zeroeth_table_offset(va)  TABLE_OFFSET(zeroeth_linear_offset(va))
+#endif
 
 /*
  * Macros to define page-tables:
diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c
index b99806af99..44942c6a4f 100644
--- a/xen/arch/arm/mm.c
+++ b/xen/arch/arm/mm.c
@@ -221,12 +221,7 @@ void dump_pt_walk(paddr_t ttbr, paddr_t addr,
 {
     static const char *level_strs[4] = { "0TH", "1ST", "2ND", "3RD" };
     const mfn_t root_mfn = maddr_to_mfn(ttbr);
-    const unsigned int offsets[4] = {
-        zeroeth_table_offset(addr),
-        first_table_offset(addr),
-        second_table_offset(addr),
-        third_table_offset(addr)
-    };
+    DECLARE_OFFSETS(offsets, addr);
     lpae_t pte, *mapping;
     unsigned int level, root_table;
 
-- 
2.17.1




 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.