From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: Sasha Levin <sashal@kernel.org>,
Atish Patra <atish.patra@wdc.com>,
linux-riscv@lists.infradead.org,
Palmer Dabbelt <palmerdabbelt@google.com>,
Anup Patel <anup@brainfault.org>
Subject: [PATCH AUTOSEL 5.10 44/45] RISC-V: Set current memblock limit
Date: Tue, 19 Jan 2021 20:26:01 -0500 [thread overview]
Message-ID: <20210120012602.769683-44-sashal@kernel.org> (raw)
In-Reply-To: <20210120012602.769683-1-sashal@kernel.org>
From: Atish Patra <atish.patra@wdc.com>
[ Upstream commit abb8e86b269604e906a6a4af7a09f04b72dbb862 ]
Currently, linux kernel can not use last 4k bytes of addressable space
because IS_ERR_VALUE macro treats those as an error. This will be an issue
for RV32 as any memblock allocator potentially allocate chunk of memory
from the end of DRAM (2GB) leading bad address error even though the
address was technically valid.
Fix this issue by limiting the memblock if available memory spans the
entire address space.
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/riscv/mm/init.c | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index e4133c20744ce..608082fb9a6c6 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -155,9 +155,10 @@ static void __init setup_initrd(void)
void __init setup_bootmem(void)
{
phys_addr_t mem_start = 0;
- phys_addr_t start, end = 0;
+ phys_addr_t start, dram_end, end = 0;
phys_addr_t vmlinux_end = __pa_symbol(&_end);
phys_addr_t vmlinux_start = __pa_symbol(&_start);
+ phys_addr_t max_mapped_addr = __pa(~(ulong)0);
u64 i;
/* Find the memory region containing the kernel */
@@ -179,7 +180,18 @@ void __init setup_bootmem(void)
/* Reserve from the start of the kernel to the end of the kernel */
memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);
- max_pfn = PFN_DOWN(memblock_end_of_DRAM());
+ dram_end = memblock_end_of_DRAM();
+
+ /*
+ * memblock allocator is not aware of the fact that last 4K bytes of
+ * the addressable memory can not be mapped because of IS_ERR_VALUE
+ * macro. Make sure that last 4k bytes are not usable by memblock
+ * if end of dram is equal to maximum addressable memory.
+ */
+ if (max_mapped_addr == (dram_end - 1))
+ memblock_set_current_limit(max_mapped_addr - 4096);
+
+ max_pfn = PFN_DOWN(dram_end);
max_low_pfn = max_pfn;
set_max_mapnr(max_low_pfn);
--
2.27.0
_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv
next prev parent reply other threads:[~2021-01-20 1:27 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20210120012602.769683-1-sashal@kernel.org>
2021-01-20 1:25 ` [PATCH AUTOSEL 5.10 14/45] riscv: Fix kernel time_init() Sasha Levin
2021-01-20 1:25 ` [PATCH AUTOSEL 5.10 15/45] riscv: Fix sifive serial driver Sasha Levin
2021-01-20 1:25 ` [PATCH AUTOSEL 5.10 16/45] riscv: Enable interrupts during syscalls with M-Mode Sasha Levin
2021-01-20 1:25 ` [PATCH AUTOSEL 5.10 22/45] riscv: cacheinfo: Fix using smp_processor_id() in preemptible Sasha Levin
2021-01-20 1:25 ` [PATCH AUTOSEL 5.10 29/45] dts: phy: fix missing mdio device and probe failure of vsc8541-01 device Sasha Levin
2021-01-20 1:25 ` [PATCH AUTOSEL 5.10 30/45] dts: phy: add GPIO number and active state used for phy reset Sasha Levin
2021-01-20 1:25 ` [PATCH AUTOSEL 5.10 31/45] riscv: defconfig: enable gpio support for HiFive Unleashed Sasha Levin
2021-01-20 1:26 ` Sasha Levin [this message]
2021-01-20 1:26 ` [PATCH AUTOSEL 5.10 45/45] RISC-V: Fix maximum allowed phsyical memory for RV32 Sasha Levin
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210120012602.769683-44-sashal@kernel.org \
--to=sashal@kernel.org \
--cc=anup@brainfault.org \
--cc=atish.patra@wdc.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-riscv@lists.infradead.org \
--cc=palmerdabbelt@google.com \
--cc=stable@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox