From: Tao Zeng <tao.zeng@amlogic.com>
Date: Wed, 2 Jan 2019 06:47:13 +0000 (+0800)
Subject: mm: fix range mistake for virt_check [1/1]
X-Git-Tag: hardkernel-4.9.236-104~1920
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=835fc3016c84b5cb18c89a29dc2e3be02de0f1f9;p=platform%2Fkernel%2Flinux-amlogic.git

mm: fix range mistake for virt_check [1/1]

PD#SWPL-3793

Problem:
Address 0xC0000000 is in lowmem, which should not be warned by

virt_check:d input of virt:c0000000
                           ~~~~~~~~
CPU: 1 PID: 5141 Comm: Binder:3297_5 Tainted: G           O    4.9.113 #1
Hardware name: Generic DT based system
[<c030e760>] (show_stack+0x20/0x24)
[<c06ee8a8>] (dump_stack+0x90/0xac)
[<c031c7b4>] (virt_check+0x64/0x68)
[<c049c45c>] (__check_object_size+0x184/0x1f8)
[<c07058c0>] (copy_page_to_iter+0x288/0x5b8)
[<c04425dc>] (generic_file_read_iter+0x390/0xa48)
[<c049f238>] (__vfs_read+0xec/0x13c)
[<c04a00e0>] (vfs_read+0x9c/0x164)
[<c05ce7e8>] (sdcardfs_read+0x28/0x50)
[<c049f194>] (__vfs_read+0x48/0x13c)
[<c04a00e0>] (vfs_read+0x9c/0x164)
[<c04a13ac>] (SyS_read+0x5c/0xbc)
[<c0308980>] (ret_fast_syscall+0x0/0x48)

Solution:
Not warning for 0xC0000000 if virt address is equal to it

Verify:
R311

Change-Id: I9a3f8efe89564f31f9a49ab4448323c93ddc761d
Signed-off-by: Tao Zeng <tao.zeng@amlogic.com>
---

diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index 7099113..4d3da37 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -1668,7 +1668,7 @@ EXPORT_SYMBOL(phys_check);
 
 unsigned long notrace virt_check(unsigned long x)
 {
-	if (scheduler_running && (x >= VMALLOC_START || x <= PAGE_OFFSET)) {
+	if (scheduler_running && (x >= VMALLOC_START || x < PAGE_OFFSET)) {
 		pr_err("bad input of virt:%lx\n", x);
 		dump_stack();
 	}