Re: [PATCH v2 2/6] ARM: use a temporary variable to hold maximum vmalloc size

From: Xu, Yanfei
Date: Fri May 28 2021 - 09:12:43 EST




On 5/28/21 6:11 PM, Russell King (Oracle) wrote:
[Please note: This e-mail is from an EXTERNAL e-mail address]

We calculate the maximum size of the vmalloc space twice in
early_vmalloc(). Use a temporary variable to hold this value.

Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Signed-off-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx>

Reviewed-by: Yanfei Xu <yanfei.xu@xxxxxxxxxxxxx>

Regards,
Yanfei
---
arch/arm/mm/mmu.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index 206c345f063e..d932c46a02e0 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -1134,6 +1134,7 @@ static unsigned long __initdata vmalloc_min =
static int __init early_vmalloc(char *arg)
{
unsigned long vmalloc_reserve = memparse(arg, NULL);
+ unsigned long vmalloc_max;

if (vmalloc_reserve < SZ_16M) {
vmalloc_reserve = SZ_16M;
@@ -1141,8 +1142,9 @@ static int __init early_vmalloc(char *arg)
vmalloc_reserve >> 20);
}

- if (vmalloc_reserve > VMALLOC_END - (PAGE_OFFSET + SZ_32M)) {
- vmalloc_reserve = VMALLOC_END - (PAGE_OFFSET + SZ_32M);
+ vmalloc_max = VMALLOC_END - (PAGE_OFFSET + SZ_32M);
+ if (vmalloc_reserve > vmalloc_max) {
+ vmalloc_reserve = vmalloc_max;
pr_warn("vmalloc area is too big, limiting to %luMB\n",
vmalloc_reserve >> 20);
}
--
2.20.1