+ revert-x86-mm-remove-unused-__set_memory_prot.patch added to mm-nonmm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: Revert "x86/mm: Remove unused __set_memory_prot()"
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     revert-x86-mm-remove-unused-__set_memory_prot.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/revert-x86-mm-remove-unused-__set_memory_prot.patch

This patch will later appear in the mm-nonmm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Coiby Xu <coxu@redhat.com>
Subject: Revert "x86/mm: Remove unused __set_memory_prot()"
Date: Fri, 2 May 2025 09:12:40 +0800

This reverts commit 693bbf2a50447353c6a47961e6a7240a823ace02 as kdump LUKS
support (CONFIG_CRASH_DM_CRYPT) depends on __set_memory_prot.

Link: https://lkml.kernel.org/r/20250502011246.99238-7-coxu@redhat.com
Signed-off-by: Coiby Xu <coxu@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: "Daniel P. Berrange" <berrange@redhat.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Jan Pazdziora <jpazdziora@redhat.com>
Cc: Liu Pingfan <kernelfans@gmail.com>
Cc: Milan Broz <gmazyland@gmail.com>
Cc: Ondrej Kozina <okozina@redhat.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/x86/include/asm/set_memory.h |    1 +
 arch/x86/mm/pat/set_memory.c      |   13 +++++++++++++
 2 files changed, 14 insertions(+)

--- a/arch/x86/include/asm/set_memory.h~revert-x86-mm-remove-unused-__set_memory_prot
+++ a/arch/x86/include/asm/set_memory.h
@@ -37,6 +37,7 @@ int set_memory_rox(unsigned long addr, i
  * The caller is required to take care of these.
  */
 
+int __set_memory_prot(unsigned long addr, int numpages, pgprot_t prot);
 int _set_memory_uc(unsigned long addr, int numpages);
 int _set_memory_wc(unsigned long addr, int numpages);
 int _set_memory_wt(unsigned long addr, int numpages);
--- a/arch/x86/mm/pat/set_memory.c~revert-x86-mm-remove-unused-__set_memory_prot
+++ a/arch/x86/mm/pat/set_memory.c
@@ -2148,6 +2148,19 @@ static inline int cpa_clear_pages_array(
 		CPA_PAGES_ARRAY, pages);
 }
 
+/*
+ * __set_memory_prot is an internal helper for callers that have been passed
+ * a pgprot_t value from upper layers and a reservation has already been taken.
+ * If you want to set the pgprot to a specific page protocol, use the
+ * set_memory_xx() functions.
+ */
+int __set_memory_prot(unsigned long addr, int numpages, pgprot_t prot)
+{
+	return change_page_attr_set_clr(&addr, numpages, prot,
+					__pgprot(~pgprot_val(prot)), 0, 0,
+					NULL);
+}
+
 int _set_memory_uc(unsigned long addr, int numpages)
 {
 	/*
_

Patches currently in -mm which might be from coxu@redhat.com are

kexec_file-allow-to-place-kexec_buf-randomly.patch
crash_dump-make-dm-crypt-keys-persist-for-the-kdump-kernel.patch
crash_dump-store-dm-crypt-keys-in-kdump-reserved-memory.patch
crash_dump-reuse-saved-dm-crypt-keys-for-cpu-memory-hot-plugging.patch
crash_dump-retrieve-dm-crypt-keys-in-kdump-kernel.patch
revert-x86-mm-remove-unused-__set_memory_prot.patch
x86-crash-pass-dm-crypt-keys-to-kdump-kernel.patch
x86-crash-make-the-page-that-stores-the-dm-crypt-keys-inaccessible.patch