FAILED: patch "[PATCH] efi/x86: Free EFI memory map only when installing a new one." failed to apply to 5.15-stable tree

FAILED: patch "[PATCH] efi/x86: Free EFI memory map only when installing a new one." failed to apply to 5.15-stable tree

[gregkh]

The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 75dde792d6f6c2d0af50278bd374bf0c512fe196
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2024062448-overspend-lucid-de35@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:

75dde792d6f6 ("efi/x86: Free EFI memory map only when installing a new one.")
d85e3e349407 ("efi: xen: Set EFI_PARAVIRT for Xen dom0 boot on all architectures")
fdc6d38d64a2 ("efi: memmap: Move manipulation routines into x86 arch tree")
1df4d1724baa ("drivers: fix typo in firmware/efi/memmap.c")
db01ea882bf6 ("efi: Correct comment on efi_memmap_alloc")
3ecc68349bba ("memblock: rename memblock_free to memblock_phys_free")
fa27717110ae ("memblock: drop memblock_free_early_nid() and memblock_free_early()")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 75dde792d6f6c2d0af50278bd374bf0c512fe196 Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ardb@kernel.org>
Date: Mon, 10 Jun 2024 16:02:13 +0200
Subject: [PATCH] efi/x86: Free EFI memory map only when installing a new one.

The logic in __efi_memmap_init() is shared between two different
execution flows:
- mapping the EFI memory map early or late into the kernel VA space, so
  that its entries can be accessed;
- the x86 specific cloning of the EFI memory map in order to insert new
  entries that are created as a result of making a memory reservation
  via a call to efi_mem_reserve().

In the former case, the underlying memory containing the kernel's view
of the EFI memory map (which may be heavily modified by the kernel
itself on x86) is not modified at all, and the only thing that changes
is the virtual mapping of this memory, which is different between early
and late boot.

In the latter case, an entirely new allocation is created that carries a
new, updated version of the kernel's view of the EFI memory map. When
installing this new version, the old version will no longer be
referenced, and if the memory was allocated by the kernel, it will leak
unless it gets freed.

The logic that implements this freeing currently lives on the code path
that is shared between these two use cases, but it should only apply to
the latter. So move it to the correct spot.

While at it, drop the dummy definition for non-x86 architectures, as
that is no longer needed.

Cc: <stable@vger.kernel.org>
Fixes: f0ef6523475f ("efi: Fix efi_memmap_alloc() leaks")
Tested-by: Ashish Kalra <Ashish.Kalra@amd.com>
Link: https://lore.kernel.org/all/36ad5079-4326-45ed-85f6-928ff76483d3@amd.com
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index 1dc600fa3ba5..481096177500 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -401,7 +401,6 @@ extern int __init efi_memmap_alloc(unsigned int num_entries,
 				   struct efi_memory_map_data *data);
 extern void __efi_memmap_free(u64 phys, unsigned long size,
 			      unsigned long flags);
-#define __efi_memmap_free __efi_memmap_free
 
 extern int __init efi_memmap_install(struct efi_memory_map_data *data);
 extern int __init efi_memmap_split_count(efi_memory_desc_t *md,
diff --git a/arch/x86/platform/efi/memmap.c b/arch/x86/platform/efi/memmap.c
index 4ef20b49eb5e..6ed1935504b9 100644
--- a/arch/x86/platform/efi/memmap.c
+++ b/arch/x86/platform/efi/memmap.c
@@ -92,12 +92,22 @@ int __init efi_memmap_alloc(unsigned int num_entries,
  */
 int __init efi_memmap_install(struct efi_memory_map_data *data)
 {
+	unsigned long size = efi.memmap.desc_size * efi.memmap.nr_map;
+	unsigned long flags = efi.memmap.flags;
+	u64 phys = efi.memmap.phys_map;
+	int ret;
+
 	efi_memmap_unmap();
 
 	if (efi_enabled(EFI_PARAVIRT))
 		return 0;
 
-	return __efi_memmap_init(data);
+	ret = __efi_memmap_init(data);
+	if (ret)
+		return ret;
+
+	__efi_memmap_free(phys, size, flags);
+	return 0;
 }
 
 /**
diff --git a/drivers/firmware/efi/memmap.c b/drivers/firmware/efi/memmap.c
index 3365944f7965..34109fd86c55 100644
--- a/drivers/firmware/efi/memmap.c
+++ b/drivers/firmware/efi/memmap.c
@@ -15,10 +15,6 @@
 #include <asm/early_ioremap.h>
 #include <asm/efi.h>
 
-#ifndef __efi_memmap_free
-#define __efi_memmap_free(phys, size, flags) do { } while (0)
-#endif
-
 /**
  * __efi_memmap_init - Common code for mapping the EFI memory map
  * @data: EFI memory map data
@@ -51,11 +47,6 @@ int __init __efi_memmap_init(struct efi_memory_map_data *data)
 		return -ENOMEM;
 	}
 
-	if (efi.memmap.flags & (EFI_MEMMAP_MEMBLOCK | EFI_MEMMAP_SLAB))
-		__efi_memmap_free(efi.memmap.phys_map,
-				  efi.memmap.desc_size * efi.memmap.nr_map,
-				  efi.memmap.flags);
-
 	map.phys_map = data->phys_map;
 	map.nr_map = data->size / data->desc_size;
 	map.map_end = map.map + data->size;

[PATCH 5.15.y 1/5] drivers: fix typo in firmware/efi/memmap.c

[Ard Biesheuvel]

From: Zheng Zhi Yuan <kevinjone25@g.ncu.edu.tw>

[ Commit 1df4d1724baafa55e9803414ebcdf1ca702bc958 upstream ]

This patch fixes the spelling error in firmware/efi/memmap.c, changing
it to the correct word.

Signed-off-by: Zheng Zhi Yuan <kevinjone25@g.ncu.edu.tw>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/firmware/efi/memmap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/firmware/efi/memmap.c b/drivers/firmware/efi/memmap.c
index 2ff1883dc788..b4070b5e4c45 100644
--- a/drivers/firmware/efi/memmap.c
+++ b/drivers/firmware/efi/memmap.c
@@ -245,7 +245,7 @@ int __init efi_memmap_install(struct efi_memory_map_data *data)
  * @range: Address range (start, end) to split around
  *
  * Returns the number of additional EFI memmap entries required to
- * accomodate @range.
+ * accommodate @range.
  */
 int __init efi_memmap_split_count(efi_memory_desc_t *md, struct range *range)
 {
-- 
2.45.2.803.g4e1b14247a-goog

[PATCH 5.15.y 2/5] efi: Correct comment on efi_memmap_alloc

[Ard Biesheuvel]

From: Liu Zixian <liuzixian4@huawei.com>

[ Commit db01ea882bf601252dad57242655da17fd9ad2f5 upstream ]

Returning zero means success now.

Signed-off-by: Liu Zixian <liuzixian4@huawei.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/firmware/efi/memmap.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/firmware/efi/memmap.c b/drivers/firmware/efi/memmap.c
index b4070b5e4c45..3aaf717aad05 100644
--- a/drivers/firmware/efi/memmap.c
+++ b/drivers/firmware/efi/memmap.c
@@ -59,8 +59,7 @@ static void __init efi_memmap_free(void)
  * Depending on whether mm_init() has already been invoked or not,
  * either memblock or "normal" page allocation is used.
  *
- * Returns the physical address of the allocated memory map on
- * success, zero on failure.
+ * Returns zero on success, a negative error code on failure.
  */
 int __init efi_memmap_alloc(unsigned int num_entries,
 		struct efi_memory_map_data *data)
-- 
2.45.2.803.g4e1b14247a-goog

[PATCH 5.15.y 3/5] efi: memmap: Move manipulation routines into x86 arch tree

[Ard Biesheuvel]

From: Ard Biesheuvel <ardb@kernel.org>

[ Commit fdc6d38d64a20c542b1867ebeb8dd03b98829336 upstream ]

The EFI memory map is a description of the memory layout as provided by
the firmware, and only x86 manipulates it in various different ways for
its own memory bookkeeping. So let's move the memmap routines that are
only used by x86 into the x86 arch tree.

[ardb: s/memblock_phys_free/memblock_free for linux-5.15.y backport]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 arch/x86/include/asm/efi.h     |  12 ++
 arch/x86/platform/efi/Makefile |   3 +-
 arch/x86/platform/efi/memmap.c | 236 ++++++++++++++++++++++++++++++++
 drivers/firmware/efi/memmap.c  | 240 ++-------------------------------
 include/linux/efi.h            |  10 +-
 5 files changed, 261 insertions(+), 240 deletions(-)
 create mode 100644 arch/x86/platform/efi/memmap.c

diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index 63158fd55856..680784da359f 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -386,6 +386,18 @@ static inline void efi_fake_memmap_early(void)
 }
 #endif
 
+extern int __init efi_memmap_alloc(unsigned int num_entries,
+				   struct efi_memory_map_data *data);
+extern void __efi_memmap_free(u64 phys, unsigned long size,
+			      unsigned long flags);
+#define __efi_memmap_free __efi_memmap_free
+
+extern int __init efi_memmap_install(struct efi_memory_map_data *data);
+extern int __init efi_memmap_split_count(efi_memory_desc_t *md,
+					 struct range *range);
+extern void __init efi_memmap_insert(struct efi_memory_map *old_memmap,
+				     void *buf, struct efi_mem_range *mem);
+
 #define arch_ima_efi_boot_mode	\
 	({ extern struct boot_params boot_params; boot_params.secure_boot; })
 
diff --git a/arch/x86/platform/efi/Makefile b/arch/x86/platform/efi/Makefile
index 84b09c230cbd..196f61fdbf28 100644
--- a/arch/x86/platform/efi/Makefile
+++ b/arch/x86/platform/efi/Makefile
@@ -3,5 +3,6 @@ OBJECT_FILES_NON_STANDARD_efi_thunk_$(BITS).o := y
 KASAN_SANITIZE := n
 GCOV_PROFILE := n
 
-obj-$(CONFIG_EFI) 		+= quirks.o efi.o efi_$(BITS).o efi_stub_$(BITS).o
+obj-$(CONFIG_EFI) 		+= memmap.o quirks.o efi.o efi_$(BITS).o \
+				   efi_stub_$(BITS).o
 obj-$(CONFIG_EFI_MIXED)		+= efi_thunk_$(BITS).o
diff --git a/arch/x86/platform/efi/memmap.c b/arch/x86/platform/efi/memmap.c
new file mode 100644
index 000000000000..620af26b55c0
--- /dev/null
+++ b/arch/x86/platform/efi/memmap.c
@@ -0,0 +1,236 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Common EFI memory map functions.
+ */
+
+#define pr_fmt(fmt) "efi: " fmt
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/efi.h>
+#include <linux/io.h>
+#include <asm/early_ioremap.h>
+#include <asm/efi.h>
+#include <linux/memblock.h>
+#include <linux/slab.h>
+
+static phys_addr_t __init __efi_memmap_alloc_early(unsigned long size)
+{
+	return memblock_phys_alloc(size, SMP_CACHE_BYTES);
+}
+
+static phys_addr_t __init __efi_memmap_alloc_late(unsigned long size)
+{
+	unsigned int order = get_order(size);
+	struct page *p = alloc_pages(GFP_KERNEL, order);
+
+	if (!p)
+		return 0;
+
+	return PFN_PHYS(page_to_pfn(p));
+}
+
+void __init __efi_memmap_free(u64 phys, unsigned long size, unsigned long flags)
+{
+	if (flags & EFI_MEMMAP_MEMBLOCK) {
+		if (slab_is_available())
+			memblock_free_late(phys, size);
+		else
+			memblock_free(phys, size);
+	} else if (flags & EFI_MEMMAP_SLAB) {
+		struct page *p = pfn_to_page(PHYS_PFN(phys));
+		unsigned int order = get_order(size);
+
+		free_pages((unsigned long) page_address(p), order);
+	}
+}
+
+/**
+ * efi_memmap_alloc - Allocate memory for the EFI memory map
+ * @num_entries: Number of entries in the allocated map.
+ * @data: efi memmap installation parameters
+ *
+ * Depending on whether mm_init() has already been invoked or not,
+ * either memblock or "normal" page allocation is used.
+ *
+ * Returns zero on success, a negative error code on failure.
+ */
+int __init efi_memmap_alloc(unsigned int num_entries,
+		struct efi_memory_map_data *data)
+{
+	/* Expect allocation parameters are zero initialized */
+	WARN_ON(data->phys_map || data->size);
+
+	data->size = num_entries * efi.memmap.desc_size;
+	data->desc_version = efi.memmap.desc_version;
+	data->desc_size = efi.memmap.desc_size;
+	data->flags &= ~(EFI_MEMMAP_SLAB | EFI_MEMMAP_MEMBLOCK);
+	data->flags |= efi.memmap.flags & EFI_MEMMAP_LATE;
+
+	if (slab_is_available()) {
+		data->flags |= EFI_MEMMAP_SLAB;
+		data->phys_map = __efi_memmap_alloc_late(data->size);
+	} else {
+		data->flags |= EFI_MEMMAP_MEMBLOCK;
+		data->phys_map = __efi_memmap_alloc_early(data->size);
+	}
+
+	if (!data->phys_map)
+		return -ENOMEM;
+	return 0;
+}
+
+/**
+ * efi_memmap_install - Install a new EFI memory map in efi.memmap
+ * @ctx: map allocation parameters (address, size, flags)
+ *
+ * Unlike efi_memmap_init_*(), this function does not allow the caller
+ * to switch from early to late mappings. It simply uses the existing
+ * mapping function and installs the new memmap.
+ *
+ * Returns zero on success, a negative error code on failure.
+ */
+int __init efi_memmap_install(struct efi_memory_map_data *data)
+{
+	efi_memmap_unmap();
+
+	return __efi_memmap_init(data);
+}
+
+/**
+ * efi_memmap_split_count - Count number of additional EFI memmap entries
+ * @md: EFI memory descriptor to split
+ * @range: Address range (start, end) to split around
+ *
+ * Returns the number of additional EFI memmap entries required to
+ * accommodate @range.
+ */
+int __init efi_memmap_split_count(efi_memory_desc_t *md, struct range *range)
+{
+	u64 m_start, m_end;
+	u64 start, end;
+	int count = 0;
+
+	start = md->phys_addr;
+	end = start + (md->num_pages << EFI_PAGE_SHIFT) - 1;
+
+	/* modifying range */
+	m_start = range->start;
+	m_end = range->end;
+
+	if (m_start <= start) {
+		/* split into 2 parts */
+		if (start < m_end && m_end < end)
+			count++;
+	}
+
+	if (start < m_start && m_start < end) {
+		/* split into 3 parts */
+		if (m_end < end)
+			count += 2;
+		/* split into 2 parts */
+		if (end <= m_end)
+			count++;
+	}
+
+	return count;
+}
+
+/**
+ * efi_memmap_insert - Insert a memory region in an EFI memmap
+ * @old_memmap: The existing EFI memory map structure
+ * @buf: Address of buffer to store new map
+ * @mem: Memory map entry to insert
+ *
+ * It is suggested that you call efi_memmap_split_count() first
+ * to see how large @buf needs to be.
+ */
+void __init efi_memmap_insert(struct efi_memory_map *old_memmap, void *buf,
+			      struct efi_mem_range *mem)
+{
+	u64 m_start, m_end, m_attr;
+	efi_memory_desc_t *md;
+	u64 start, end;
+	void *old, *new;
+
+	/* modifying range */
+	m_start = mem->range.start;
+	m_end = mem->range.end;
+	m_attr = mem->attribute;
+
+	/*
+	 * The EFI memory map deals with regions in EFI_PAGE_SIZE
+	 * units. Ensure that the region described by 'mem' is aligned
+	 * correctly.
+	 */
+	if (!IS_ALIGNED(m_start, EFI_PAGE_SIZE) ||
+	    !IS_ALIGNED(m_end + 1, EFI_PAGE_SIZE)) {
+		WARN_ON(1);
+		return;
+	}
+
+	for (old = old_memmap->map, new = buf;
+	     old < old_memmap->map_end;
+	     old += old_memmap->desc_size, new += old_memmap->desc_size) {
+
+		/* copy original EFI memory descriptor */
+		memcpy(new, old, old_memmap->desc_size);
+		md = new;
+		start = md->phys_addr;
+		end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - 1;
+
+		if (m_start <= start && end <= m_end)
+			md->attribute |= m_attr;
+
+		if (m_start <= start &&
+		    (start < m_end && m_end < end)) {
+			/* first part */
+			md->attribute |= m_attr;
+			md->num_pages = (m_end - md->phys_addr + 1) >>
+				EFI_PAGE_SHIFT;
+			/* latter part */
+			new += old_memmap->desc_size;
+			memcpy(new, old, old_memmap->desc_size);
+			md = new;
+			md->phys_addr = m_end + 1;
+			md->num_pages = (end - md->phys_addr + 1) >>
+				EFI_PAGE_SHIFT;
+		}
+
+		if ((start < m_start && m_start < end) && m_end < end) {
+			/* first part */
+			md->num_pages = (m_start - md->phys_addr) >>
+				EFI_PAGE_SHIFT;
+			/* middle part */
+			new += old_memmap->desc_size;
+			memcpy(new, old, old_memmap->desc_size);
+			md = new;
+			md->attribute |= m_attr;
+			md->phys_addr = m_start;
+			md->num_pages = (m_end - m_start + 1) >>
+				EFI_PAGE_SHIFT;
+			/* last part */
+			new += old_memmap->desc_size;
+			memcpy(new, old, old_memmap->desc_size);
+			md = new;
+			md->phys_addr = m_end + 1;
+			md->num_pages = (end - m_end) >>
+				EFI_PAGE_SHIFT;
+		}
+
+		if ((start < m_start && m_start < end) &&
+		    (end <= m_end)) {
+			/* first part */
+			md->num_pages = (m_start - md->phys_addr) >>
+				EFI_PAGE_SHIFT;
+			/* latter part */
+			new += old_memmap->desc_size;
+			memcpy(new, old, old_memmap->desc_size);
+			md = new;
+			md->phys_addr = m_start;
+			md->num_pages = (end - md->phys_addr + 1) >>
+				EFI_PAGE_SHIFT;
+			md->attribute |= m_attr;
+		}
+	}
+}
diff --git a/drivers/firmware/efi/memmap.c b/drivers/firmware/efi/memmap.c
index 3aaf717aad05..e6256c48284e 100644
--- a/drivers/firmware/efi/memmap.c
+++ b/drivers/firmware/efi/memmap.c
@@ -9,82 +9,15 @@
 #include <linux/kernel.h>
 #include <linux/efi.h>
 #include <linux/io.h>
-#include <asm/early_ioremap.h>
 #include <linux/memblock.h>
 #include <linux/slab.h>
 
-static phys_addr_t __init __efi_memmap_alloc_early(unsigned long size)
-{
-	return memblock_phys_alloc(size, SMP_CACHE_BYTES);
-}
-
-static phys_addr_t __init __efi_memmap_alloc_late(unsigned long size)
-{
-	unsigned int order = get_order(size);
-	struct page *p = alloc_pages(GFP_KERNEL, order);
-
-	if (!p)
-		return 0;
-
-	return PFN_PHYS(page_to_pfn(p));
-}
-
-void __init __efi_memmap_free(u64 phys, unsigned long size, unsigned long flags)
-{
-	if (flags & EFI_MEMMAP_MEMBLOCK) {
-		if (slab_is_available())
-			memblock_free_late(phys, size);
-		else
-			memblock_free(phys, size);
-	} else if (flags & EFI_MEMMAP_SLAB) {
-		struct page *p = pfn_to_page(PHYS_PFN(phys));
-		unsigned int order = get_order(size);
-
-		free_pages((unsigned long) page_address(p), order);
-	}
-}
-
-static void __init efi_memmap_free(void)
-{
-	__efi_memmap_free(efi.memmap.phys_map,
-			efi.memmap.desc_size * efi.memmap.nr_map,
-			efi.memmap.flags);
-}
-
-/**
- * efi_memmap_alloc - Allocate memory for the EFI memory map
- * @num_entries: Number of entries in the allocated map.
- * @data: efi memmap installation parameters
- *
- * Depending on whether mm_init() has already been invoked or not,
- * either memblock or "normal" page allocation is used.
- *
- * Returns zero on success, a negative error code on failure.
- */
-int __init efi_memmap_alloc(unsigned int num_entries,
-		struct efi_memory_map_data *data)
-{
-	/* Expect allocation parameters are zero initialized */
-	WARN_ON(data->phys_map || data->size);
-
-	data->size = num_entries * efi.memmap.desc_size;
-	data->desc_version = efi.memmap.desc_version;
-	data->desc_size = efi.memmap.desc_size;
-	data->flags &= ~(EFI_MEMMAP_SLAB | EFI_MEMMAP_MEMBLOCK);
-	data->flags |= efi.memmap.flags & EFI_MEMMAP_LATE;
-
-	if (slab_is_available()) {
-		data->flags |= EFI_MEMMAP_SLAB;
-		data->phys_map = __efi_memmap_alloc_late(data->size);
-	} else {
-		data->flags |= EFI_MEMMAP_MEMBLOCK;
-		data->phys_map = __efi_memmap_alloc_early(data->size);
-	}
+#include <asm/early_ioremap.h>
+#include <asm/efi.h>
 
-	if (!data->phys_map)
-		return -ENOMEM;
-	return 0;
-}
+#ifndef __efi_memmap_free
+#define __efi_memmap_free(phys, size, flags) do { } while (0)
+#endif
 
 /**
  * __efi_memmap_init - Common code for mapping the EFI memory map
@@ -101,7 +34,7 @@ int __init efi_memmap_alloc(unsigned int num_entries,
  *
  * Returns zero on success, a negative error code on failure.
  */
-static int __init __efi_memmap_init(struct efi_memory_map_data *data)
+int __init __efi_memmap_init(struct efi_memory_map_data *data)
 {
 	struct efi_memory_map map;
 	phys_addr_t phys_map;
@@ -121,8 +54,10 @@ static int __init __efi_memmap_init(struct efi_memory_map_data *data)
 		return -ENOMEM;
 	}
 
-	/* NOP if data->flags & (EFI_MEMMAP_MEMBLOCK | EFI_MEMMAP_SLAB) == 0 */
-	efi_memmap_free();
+	if (efi.memmap.flags & (EFI_MEMMAP_MEMBLOCK | EFI_MEMMAP_SLAB))
+		__efi_memmap_free(efi.memmap.phys_map,
+				  efi.memmap.desc_size * efi.memmap.nr_map,
+				  efi.memmap.flags);
 
 	map.phys_map = data->phys_map;
 	map.nr_map = data->size / data->desc_size;
@@ -220,158 +155,3 @@ int __init efi_memmap_init_late(phys_addr_t addr, unsigned long size)
 
 	return __efi_memmap_init(&data);
 }
-
-/**
- * efi_memmap_install - Install a new EFI memory map in efi.memmap
- * @ctx: map allocation parameters (address, size, flags)
- *
- * Unlike efi_memmap_init_*(), this function does not allow the caller
- * to switch from early to late mappings. It simply uses the existing
- * mapping function and installs the new memmap.
- *
- * Returns zero on success, a negative error code on failure.
- */
-int __init efi_memmap_install(struct efi_memory_map_data *data)
-{
-	efi_memmap_unmap();
-
-	return __efi_memmap_init(data);
-}
-
-/**
- * efi_memmap_split_count - Count number of additional EFI memmap entries
- * @md: EFI memory descriptor to split
- * @range: Address range (start, end) to split around
- *
- * Returns the number of additional EFI memmap entries required to
- * accommodate @range.
- */
-int __init efi_memmap_split_count(efi_memory_desc_t *md, struct range *range)
-{
-	u64 m_start, m_end;
-	u64 start, end;
-	int count = 0;
-
-	start = md->phys_addr;
-	end = start + (md->num_pages << EFI_PAGE_SHIFT) - 1;
-
-	/* modifying range */
-	m_start = range->start;
-	m_end = range->end;
-
-	if (m_start <= start) {
-		/* split into 2 parts */
-		if (start < m_end && m_end < end)
-			count++;
-	}
-
-	if (start < m_start && m_start < end) {
-		/* split into 3 parts */
-		if (m_end < end)
-			count += 2;
-		/* split into 2 parts */
-		if (end <= m_end)
-			count++;
-	}
-
-	return count;
-}
-
-/**
- * efi_memmap_insert - Insert a memory region in an EFI memmap
- * @old_memmap: The existing EFI memory map structure
- * @buf: Address of buffer to store new map
- * @mem: Memory map entry to insert
- *
- * It is suggested that you call efi_memmap_split_count() first
- * to see how large @buf needs to be.
- */
-void __init efi_memmap_insert(struct efi_memory_map *old_memmap, void *buf,
-			      struct efi_mem_range *mem)
-{
-	u64 m_start, m_end, m_attr;
-	efi_memory_desc_t *md;
-	u64 start, end;
-	void *old, *new;
-
-	/* modifying range */
-	m_start = mem->range.start;
-	m_end = mem->range.end;
-	m_attr = mem->attribute;
-
-	/*
-	 * The EFI memory map deals with regions in EFI_PAGE_SIZE
-	 * units. Ensure that the region described by 'mem' is aligned
-	 * correctly.
-	 */
-	if (!IS_ALIGNED(m_start, EFI_PAGE_SIZE) ||
-	    !IS_ALIGNED(m_end + 1, EFI_PAGE_SIZE)) {
-		WARN_ON(1);
-		return;
-	}
-
-	for (old = old_memmap->map, new = buf;
-	     old < old_memmap->map_end;
-	     old += old_memmap->desc_size, new += old_memmap->desc_size) {
-
-		/* copy original EFI memory descriptor */
-		memcpy(new, old, old_memmap->desc_size);
-		md = new;
-		start = md->phys_addr;
-		end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - 1;
-
-		if (m_start <= start && end <= m_end)
-			md->attribute |= m_attr;
-
-		if (m_start <= start &&
-		    (start < m_end && m_end < end)) {
-			/* first part */
-			md->attribute |= m_attr;
-			md->num_pages = (m_end - md->phys_addr + 1) >>
-				EFI_PAGE_SHIFT;
-			/* latter part */
-			new += old_memmap->desc_size;
-			memcpy(new, old, old_memmap->desc_size);
-			md = new;
-			md->phys_addr = m_end + 1;
-			md->num_pages = (end - md->phys_addr + 1) >>
-				EFI_PAGE_SHIFT;
-		}
-
-		if ((start < m_start && m_start < end) && m_end < end) {
-			/* first part */
-			md->num_pages = (m_start - md->phys_addr) >>
-				EFI_PAGE_SHIFT;
-			/* middle part */
-			new += old_memmap->desc_size;
-			memcpy(new, old, old_memmap->desc_size);
-			md = new;
-			md->attribute |= m_attr;
-			md->phys_addr = m_start;
-			md->num_pages = (m_end - m_start + 1) >>
-				EFI_PAGE_SHIFT;
-			/* last part */
-			new += old_memmap->desc_size;
-			memcpy(new, old, old_memmap->desc_size);
-			md = new;
-			md->phys_addr = m_end + 1;
-			md->num_pages = (end - m_end) >>
-				EFI_PAGE_SHIFT;
-		}
-
-		if ((start < m_start && m_start < end) &&
-		    (end <= m_end)) {
-			/* first part */
-			md->num_pages = (m_start - md->phys_addr) >>
-				EFI_PAGE_SHIFT;
-			/* latter part */
-			new += old_memmap->desc_size;
-			memcpy(new, old, old_memmap->desc_size);
-			md = new;
-			md->phys_addr = m_start;
-			md->num_pages = (end - md->phys_addr + 1) >>
-				EFI_PAGE_SHIFT;
-			md->attribute |= m_attr;
-		}
-	}
-}
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 5598fc348c69..7e396e31e0b7 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -627,18 +627,10 @@ static inline efi_status_t efi_query_variable_store(u32 attributes,
 #endif
 extern void __iomem *efi_lookup_mapped_addr(u64 phys_addr);
 
-extern int __init efi_memmap_alloc(unsigned int num_entries,
-				   struct efi_memory_map_data *data);
-extern void __efi_memmap_free(u64 phys, unsigned long size,
-			      unsigned long flags);
+extern int __init __efi_memmap_init(struct efi_memory_map_data *data);
 extern int __init efi_memmap_init_early(struct efi_memory_map_data *data);
 extern int __init efi_memmap_init_late(phys_addr_t addr, unsigned long size);
 extern void __init efi_memmap_unmap(void);
-extern int __init efi_memmap_install(struct efi_memory_map_data *data);
-extern int __init efi_memmap_split_count(efi_memory_desc_t *md,
-					 struct range *range);
-extern void __init efi_memmap_insert(struct efi_memory_map *old_memmap,
-				     void *buf, struct efi_mem_range *mem);
 
 #ifdef CONFIG_EFI_ESRT
 extern void __init efi_esrt_init(void);
-- 
2.45.2.803.g4e1b14247a-goog

[PATCH 5.15.y 4/5] efi: xen: Set EFI_PARAVIRT for Xen dom0 boot on all architectures

[Ard Biesheuvel]

From: Ard Biesheuvel <ardb@kernel.org>

[ Commit d85e3e34940788578eeffd94e8b7e1d28e7278e9 upstream ]

Currently, the EFI_PARAVIRT flag is only used by Xen dom0 boot on x86,
even though other architectures also support pseudo-EFI boot, where the
core kernel is invoked directly and provided with a set of data tables
that resemble the ones constructed by the EFI stub, which never actually
runs in that case.

Let's fix this inconsistency, and always set this flag when booting dom0
via the EFI boot path. Note that Xen on x86 does not provide the EFI
memory map in this case, whereas other architectures do, so move the
associated EFI_PARAVIRT check into the x86 platform code.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 arch/x86/platform/efi/efi.c      | 8 +++++---
 arch/x86/platform/efi/memmap.c   | 3 +++
 drivers/firmware/efi/fdtparams.c | 4 ++++
 drivers/firmware/efi/memmap.c    | 3 ---
 4 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 147c30a81f15..da17de248387 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -234,9 +234,11 @@ int __init efi_memblock_x86_reserve_range(void)
 	data.desc_size		= e->efi_memdesc_size;
 	data.desc_version	= e->efi_memdesc_version;
 
-	rv = efi_memmap_init_early(&data);
-	if (rv)
-		return rv;
+	if (!efi_enabled(EFI_PARAVIRT)) {
+		rv = efi_memmap_init_early(&data);
+		if (rv)
+			return rv;
+	}
 
 	if (add_efi_memmap || do_efi_soft_reserve())
 		do_add_efi_memmap();
diff --git a/arch/x86/platform/efi/memmap.c b/arch/x86/platform/efi/memmap.c
index 620af26b55c0..241464b6dd03 100644
--- a/arch/x86/platform/efi/memmap.c
+++ b/arch/x86/platform/efi/memmap.c
@@ -94,6 +94,9 @@ int __init efi_memmap_install(struct efi_memory_map_data *data)
 {
 	efi_memmap_unmap();
 
+	if (efi_enabled(EFI_PARAVIRT))
+		return 0;
+
 	return __efi_memmap_init(data);
 }
 
diff --git a/drivers/firmware/efi/fdtparams.c b/drivers/firmware/efi/fdtparams.c
index e901f8564ca0..0ec83ba58097 100644
--- a/drivers/firmware/efi/fdtparams.c
+++ b/drivers/firmware/efi/fdtparams.c
@@ -30,11 +30,13 @@ static __initconst const char name[][22] = {
 
 static __initconst const struct {
 	const char	path[17];
+	u8		paravirt;
 	const char	params[PARAMCOUNT][26];
 } dt_params[] = {
 	{
 #ifdef CONFIG_XEN    //  <-------17------>
 		.path = "/hypervisor/uefi",
+		.paravirt = 1,
 		.params = {
 			[SYSTAB] = "xen,uefi-system-table",
 			[MMBASE] = "xen,uefi-mmap-start",
@@ -121,6 +123,8 @@ u64 __init efi_get_fdt_params(struct efi_memory_map_data *mm)
 			pr_err("Can't find property '%s' in DT!\n", pname);
 			return 0;
 		}
+		if (dt_params[i].paravirt)
+			set_bit(EFI_PARAVIRT, &efi.flags);
 		return systab;
 	}
 notfound:
diff --git a/drivers/firmware/efi/memmap.c b/drivers/firmware/efi/memmap.c
index e6256c48284e..a1180461a445 100644
--- a/drivers/firmware/efi/memmap.c
+++ b/drivers/firmware/efi/memmap.c
@@ -39,9 +39,6 @@ int __init __efi_memmap_init(struct efi_memory_map_data *data)
 	struct efi_memory_map map;
 	phys_addr_t phys_map;
 
-	if (efi_enabled(EFI_PARAVIRT))
-		return 0;
-
 	phys_map = data->phys_map;
 
 	if (data->flags & EFI_MEMMAP_LATE)
-- 
2.45.2.803.g4e1b14247a-goog

[PATCH 5.15.y 5/5] efi/x86: Free EFI memory map only when installing a new one.

[Ard Biesheuvel]

From: Ard Biesheuvel <ardb@kernel.org>

[ Commit 75dde792d6f6c2d0af50278bd374bf0c512fe196 upstream ]

The logic in __efi_memmap_init() is shared between two different
execution flows:
- mapping the EFI memory map early or late into the kernel VA space, so
  that its entries can be accessed;
- the x86 specific cloning of the EFI memory map in order to insert new
  entries that are created as a result of making a memory reservation
  via a call to efi_mem_reserve().

In the former case, the underlying memory containing the kernel's view
of the EFI memory map (which may be heavily modified by the kernel
itself on x86) is not modified at all, and the only thing that changes
is the virtual mapping of this memory, which is different between early
and late boot.

In the latter case, an entirely new allocation is created that carries a
new, updated version of the kernel's view of the EFI memory map. When
installing this new version, the old version will no longer be
referenced, and if the memory was allocated by the kernel, it will leak
unless it gets freed.

The logic that implements this freeing currently lives on the code path
that is shared between these two use cases, but it should only apply to
the latter. So move it to the correct spot.

While at it, drop the dummy definition for non-x86 architectures, as
that is no longer needed.

Cc: <stable@vger.kernel.org>
Fixes: f0ef6523475f ("efi: Fix efi_memmap_alloc() leaks")
Tested-by: Ashish Kalra <Ashish.Kalra@amd.com>
Link: https://lore.kernel.org/all/36ad5079-4326-45ed-85f6-928ff76483d3@amd.com
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 arch/x86/include/asm/efi.h     |  1 -
 arch/x86/platform/efi/memmap.c | 12 +++++++++++-
 drivers/firmware/efi/memmap.c  |  9 ---------
 3 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index 680784da359f..e7c07a182ebd 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -390,7 +390,6 @@ extern int __init efi_memmap_alloc(unsigned int num_entries,
 				   struct efi_memory_map_data *data);
 extern void __efi_memmap_free(u64 phys, unsigned long size,
 			      unsigned long flags);
-#define __efi_memmap_free __efi_memmap_free
 
 extern int __init efi_memmap_install(struct efi_memory_map_data *data);
 extern int __init efi_memmap_split_count(efi_memory_desc_t *md,
diff --git a/arch/x86/platform/efi/memmap.c b/arch/x86/platform/efi/memmap.c
index 241464b6dd03..872d310c426e 100644
--- a/arch/x86/platform/efi/memmap.c
+++ b/arch/x86/platform/efi/memmap.c
@@ -92,12 +92,22 @@ int __init efi_memmap_alloc(unsigned int num_entries,
  */
 int __init efi_memmap_install(struct efi_memory_map_data *data)
 {
+	unsigned long size = efi.memmap.desc_size * efi.memmap.nr_map;
+	unsigned long flags = efi.memmap.flags;
+	u64 phys = efi.memmap.phys_map;
+	int ret;
+
 	efi_memmap_unmap();
 
 	if (efi_enabled(EFI_PARAVIRT))
 		return 0;
 
-	return __efi_memmap_init(data);
+	ret = __efi_memmap_init(data);
+	if (ret)
+		return ret;
+
+	__efi_memmap_free(phys, size, flags);
+	return 0;
 }
 
 /**
diff --git a/drivers/firmware/efi/memmap.c b/drivers/firmware/efi/memmap.c
index a1180461a445..77dd20f9df31 100644
--- a/drivers/firmware/efi/memmap.c
+++ b/drivers/firmware/efi/memmap.c
@@ -15,10 +15,6 @@
 #include <asm/early_ioremap.h>
 #include <asm/efi.h>
 
-#ifndef __efi_memmap_free
-#define __efi_memmap_free(phys, size, flags) do { } while (0)
-#endif
-
 /**
  * __efi_memmap_init - Common code for mapping the EFI memory map
  * @data: EFI memory map data
@@ -51,11 +47,6 @@ int __init __efi_memmap_init(struct efi_memory_map_data *data)
 		return -ENOMEM;
 	}
 
-	if (efi.memmap.flags & (EFI_MEMMAP_MEMBLOCK | EFI_MEMMAP_SLAB))
-		__efi_memmap_free(efi.memmap.phys_map,
-				  efi.memmap.desc_size * efi.memmap.nr_map,
-				  efi.memmap.flags);
-
 	map.phys_map = data->phys_map;
 	map.nr_map = data->size / data->desc_size;
 	map.map_end = map.map + data->size;
-- 
2.45.2.803.g4e1b14247a-goog