linux-kernel - [tip: x86/sgx] x86/sgx: Do not update sgx_nr_free_pages in sgx_setup_epc

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Message-ID: <161789600921.29796.11515347973623709051.tip-bot2@tip-bot2>
Date:   Thu, 08 Apr 2021 15:33:29 -0000
From:   "tip-bot2 for Jarkko Sakkinen" <tip-bot2@...utronix.de>
To:     linux-tip-commits@...r.kernel.org
Cc:     Jarkko Sakkinen <jarkko@...nel.org>, Borislav Petkov <bp@...e.de>,
        x86@...nel.org, linux-kernel@...r.kernel.org
Subject: [tip: x86/sgx] x86/sgx: Do not update sgx_nr_free_pages in
 sgx_setup_epc_section()

The following commit has been merged into the x86/sgx branch of tip:

Commit-ID:     ae40aaf6bdbf0354a75b8284a0de453fcf5f4d32
Gitweb:        https://git.kernel.org/tip/ae40aaf6bdbf0354a75b8284a0de453fcf5f4d32
Author:        Jarkko Sakkinen <jarkko@...nel.org>
AuthorDate:    Thu, 08 Apr 2021 12:29:24 +03:00
Committer:     Borislav Petkov <bp@...e.de>
CommitterDate: Thu, 08 Apr 2021 17:24:42 +02:00

x86/sgx: Do not update sgx_nr_free_pages in sgx_setup_epc_section()

The commit in Fixes: changed the SGX EPC page sanitization to end up in
sgx_free_epc_page() which puts clean and sanitized pages on the free
list.

This was done for the reason that it is best to keep the logic to assign
available-for-use EPC pages to the correct NUMA lists in a single
location.

sgx_nr_free_pages is also incremented by sgx_free_epc_pages() but those
pages which are being added there per EPC section do not belong to the
free list yet because they haven't been sanitized yet - they land on the
dirty list first and the sanitization happens later when ksgxd starts
massaging them.

So remove that addition there and have sgx_free_epc_page() do that
solely.

 [ bp: Sanitize commit message too. ]

Fixes: 51ab30eb2ad4 ("x86/sgx: Replace section->init_laundry_list with sgx_dirty_page_list")
Signed-off-by: Jarkko Sakkinen <jarkko@...nel.org>
Signed-off-by: Borislav Petkov <bp@...e.de>
Link: https://lkml.kernel.org/r/20210408092924.7032-1-jarkko@kernel.org
---
 arch/x86/kernel/cpu/sgx/main.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c
index 92cb11d..ad90474 100644
--- a/arch/x86/kernel/cpu/sgx/main.c
+++ b/arch/x86/kernel/cpu/sgx/main.c
@@ -656,7 +656,6 @@ static bool __init sgx_setup_epc_section(u64 phys_addr, u64 size,
 		list_add_tail(&section->pages[i].list, &sgx_dirty_page_list);
 	}

-	sgx_nr_free_pages += nr_pages;
 	return true;
 }