linux: add patches from greg ungerer

5 files changed, 305 insertions, 0 deletions

diff --git a/target/linux/patches/6.1.49/armnommu-fix-elf-fdpic-personality.patch b/target/linux/patches/6.1.49/armnommu-fix-elf-fdpic-personality.patch
new file mode 100644
index 000000000..c7037f4f8
--- /dev/null
+++ b/target/linux/patches/6.1.49/armnommu-fix-elf-fdpic-personality.patch
@@ -0,0 +1,45 @@
+From ab7647c2b04501297c50ce7cdb6f6895b9582d22 Mon Sep 17 00:00:00 2001
+From: Greg Ungerer <gerg@kernel.org>
+Date: Fri, 21 Apr 2023 00:21:38 +1000
+Subject: [PATCH] fs: binfmt_elf_efpic: fix personality for non-fdpic ELF
+
+The elf-fdpic loader hard sets the process personality to either
+PER_LINUX_FDPIC for true elf-fdpic binaries or to PER_LINUX for
+normal ELF binaries (in this case they would be constant displacement
+compiled with -pie for example). The problem with that is that it
+will lose any other bits that may be in the ELF header personality
+("the "bug emulation" bits).
+
+On the ARM architecture the ADDR_LIMIT_32BIT flag is used to signify
+a normal 32bit binary - as opposed to a legacy 26bit address binary.
+This matters since start_thread() will set the ARM CPSR register as
+required based on this flag. If the elf-fdpic loader has lost this
+bit the process will be mis-configured and crash out pretty quickly.
+
+Modify elf-fdpic loaders personality setting for ELF binaries so that
+it preserves the upper three bytes by using the SET_PERSONALITY macro
+to set it. This macro in the generic case sets PER_LINUX but and
+preserves the upper bytes. Architectures can override this for their
+specific use case, and ARM does exactly this.
+
+Signed-off-by: Greg Ungerer <gerg@kernel.org>
+---
+ fs/binfmt_elf_fdpic.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
+index a05eafcacfb2..f29ae1d96fd7 100644
+--- a/fs/binfmt_elf_fdpic.c
++++ b/fs/binfmt_elf_fdpic.c
+@@ -348,7 +348,7 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm)
+ 	if (elf_check_fdpic(&exec_params.hdr))
+ 		set_personality(PER_LINUX_FDPIC);
+ 	else
+-		set_personality(PER_LINUX);
++		SET_PERSONALITY(exec_params.hdr);
+ 	if (elf_read_implies_exec(&exec_params.hdr, executable_stack))
+ 		current->personality |= READ_IMPLIES_EXEC;
+ 
+-- 
+2.25.1
+
diff --git a/target/linux/patches/6.1.49/armnommu-fix-thread-registers.patch b/target/linux/patches/6.1.49/armnommu-fix-thread-registers.patch
new file mode 100644
index 000000000..8ab2196dc
--- /dev/null
+++ b/target/linux/patches/6.1.49/armnommu-fix-thread-registers.patch
@@ -0,0 +1,57 @@
+From 1410ebe685f13c1699a16bf147ae1332e7fd1983 Mon Sep 17 00:00:00 2001
+From: Greg Ungerer <gerg@kernel.org>
+Date: Thu, 20 Apr 2023 09:52:08 +1000
+Subject: [PATCH] ARM: start_thread: restore registers on ELF load for noMMU
+
+The binfmt_elf-fdpic loader is capable of loading constant displacement
+ELF format binaries (like those compiled -pie) on noMMU systems as well
+as elf-fdpic format binaries. The traditional ELF loader cannot be
+enabled on noMMU systems.
+
+Commit 5e588114329c ("ARM: start_thread(): don't always clear all regs")
+fixed the start_thread() code so that it maintains the required
+elf-fdpic registers through to the new process, but it only does that if
+current has its personality FDPIC_FUNCPTRS bit set. That is true for
+elf-fdpic format binaries but will not be true for non-fdpic ELF
+binaries.
+
+Modify the test of the FDPIC_FUNCPTRS personality bit to also carry out
+the register restore if this is a noMMU system. This is not perfect,
+since it will also preserve these registers on noMMU systems for all
+binary format types (could be flat format for example). That won't break
+anything, but it is potentially leaking some information into the new
+process. But for the noMMU case we need those start time registers set to
+be able to finalize the runtime loading of the -pie style ELF binary
+(carry out its segment and dynamic relocation processing).
+
+Unfortunately the FDPIC_FUNCPTRS flag cannot just be enabled for all
+elf-fdpic loaded binaries. That personality bit is used for other things
+like the controlling the changed behavior for signal handling.
+
+There is no change in behavior for normal ELF loading on MMU systems.
+A -pie style ELF binary built for noMMU systems can be load and run using
+the usual ELF loader on an MMU system (elf-fdpic loader not required in
+this case).
+
+Signed-off-by: Greg Ungerer <gerg@kernel.org>
+---
+ arch/arm/include/asm/processor.h | 3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+diff --git a/arch/arm/include/asm/processor.h b/arch/arm/include/asm/processor.h
+index 326864f79d18..5074cc3ae4e1 100644
+--- a/arch/arm/include/asm/processor.h
++++ b/arch/arm/include/asm/processor.h
+@@ -60,7 +60,8 @@ static inline void arch_thread_struct_whitelist(unsigned long *offset,
+ 	}								\
+ 	memset(regs->uregs, 0, sizeof(regs->uregs));			\
+ 	if (IS_ENABLED(CONFIG_BINFMT_ELF_FDPIC) &&			\
+-	    current->personality & FDPIC_FUNCPTRS) {			\
++	    ((! IS_ENABLED(CONFIG_MMU)) ||				\
++	     current->personality & FDPIC_FUNCPTRS)) {			\
+ 		regs->ARM_r7 = r7;					\
+ 		regs->ARM_r8 = r8;					\
+ 		regs->ARM_r9 = r9;					\
+-- 
+2.25.1
+
diff --git a/target/linux/patches/6.4.12/armnommu-fix-elf-fdpic-personality.patch b/target/linux/patches/6.4.12/armnommu-fix-elf-fdpic-personality.patch
new file mode 100644
index 000000000..c7037f4f8
--- /dev/null
+++ b/target/linux/patches/6.4.12/armnommu-fix-elf-fdpic-personality.patch
@@ -0,0 +1,45 @@
+From ab7647c2b04501297c50ce7cdb6f6895b9582d22 Mon Sep 17 00:00:00 2001
+From: Greg Ungerer <gerg@kernel.org>
+Date: Fri, 21 Apr 2023 00:21:38 +1000
+Subject: [PATCH] fs: binfmt_elf_efpic: fix personality for non-fdpic ELF
+
+The elf-fdpic loader hard sets the process personality to either
+PER_LINUX_FDPIC for true elf-fdpic binaries or to PER_LINUX for
+normal ELF binaries (in this case they would be constant displacement
+compiled with -pie for example). The problem with that is that it
+will lose any other bits that may be in the ELF header personality
+("the "bug emulation" bits).
+
+On the ARM architecture the ADDR_LIMIT_32BIT flag is used to signify
+a normal 32bit binary - as opposed to a legacy 26bit address binary.
+This matters since start_thread() will set the ARM CPSR register as
+required based on this flag. If the elf-fdpic loader has lost this
+bit the process will be mis-configured and crash out pretty quickly.
+
+Modify elf-fdpic loaders personality setting for ELF binaries so that
+it preserves the upper three bytes by using the SET_PERSONALITY macro
+to set it. This macro in the generic case sets PER_LINUX but and
+preserves the upper bytes. Architectures can override this for their
+specific use case, and ARM does exactly this.
+
+Signed-off-by: Greg Ungerer <gerg@kernel.org>
+---
+ fs/binfmt_elf_fdpic.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
+index a05eafcacfb2..f29ae1d96fd7 100644
+--- a/fs/binfmt_elf_fdpic.c
++++ b/fs/binfmt_elf_fdpic.c
+@@ -348,7 +348,7 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm)
+ 	if (elf_check_fdpic(&exec_params.hdr))
+ 		set_personality(PER_LINUX_FDPIC);
+ 	else
+-		set_personality(PER_LINUX);
++		SET_PERSONALITY(exec_params.hdr);
+ 	if (elf_read_implies_exec(&exec_params.hdr, executable_stack))
+ 		current->personality |= READ_IMPLIES_EXEC;
+ 
+-- 
+2.25.1
+
diff --git a/target/linux/patches/6.4.12/armnommu-fix-thread-registers.patch b/target/linux/patches/6.4.12/armnommu-fix-thread-registers.patch
new file mode 100644
index 000000000..8ab2196dc
--- /dev/null
+++ b/target/linux/patches/6.4.12/armnommu-fix-thread-registers.patch
@@ -0,0 +1,57 @@
+From 1410ebe685f13c1699a16bf147ae1332e7fd1983 Mon Sep 17 00:00:00 2001
+From: Greg Ungerer <gerg@kernel.org>
+Date: Thu, 20 Apr 2023 09:52:08 +1000
+Subject: [PATCH] ARM: start_thread: restore registers on ELF load for noMMU
+
+The binfmt_elf-fdpic loader is capable of loading constant displacement
+ELF format binaries (like those compiled -pie) on noMMU systems as well
+as elf-fdpic format binaries. The traditional ELF loader cannot be
+enabled on noMMU systems.
+
+Commit 5e588114329c ("ARM: start_thread(): don't always clear all regs")
+fixed the start_thread() code so that it maintains the required
+elf-fdpic registers through to the new process, but it only does that if
+current has its personality FDPIC_FUNCPTRS bit set. That is true for
+elf-fdpic format binaries but will not be true for non-fdpic ELF
+binaries.
+
+Modify the test of the FDPIC_FUNCPTRS personality bit to also carry out
+the register restore if this is a noMMU system. This is not perfect,
+since it will also preserve these registers on noMMU systems for all
+binary format types (could be flat format for example). That won't break
+anything, but it is potentially leaking some information into the new
+process. But for the noMMU case we need those start time registers set to
+be able to finalize the runtime loading of the -pie style ELF binary
+(carry out its segment and dynamic relocation processing).
+
+Unfortunately the FDPIC_FUNCPTRS flag cannot just be enabled for all
+elf-fdpic loaded binaries. That personality bit is used for other things
+like the controlling the changed behavior for signal handling.
+
+There is no change in behavior for normal ELF loading on MMU systems.
+A -pie style ELF binary built for noMMU systems can be load and run using
+the usual ELF loader on an MMU system (elf-fdpic loader not required in
+this case).
+
+Signed-off-by: Greg Ungerer <gerg@kernel.org>
+---
+ arch/arm/include/asm/processor.h | 3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+diff --git a/arch/arm/include/asm/processor.h b/arch/arm/include/asm/processor.h
+index 326864f79d18..5074cc3ae4e1 100644
+--- a/arch/arm/include/asm/processor.h
++++ b/arch/arm/include/asm/processor.h
+@@ -60,7 +60,8 @@ static inline void arch_thread_struct_whitelist(unsigned long *offset,
+ 	}								\
+ 	memset(regs->uregs, 0, sizeof(regs->uregs));			\
+ 	if (IS_ENABLED(CONFIG_BINFMT_ELF_FDPIC) &&			\
+-	    current->personality & FDPIC_FUNCPTRS) {			\
++	    ((! IS_ENABLED(CONFIG_MMU)) ||				\
++	     current->personality & FDPIC_FUNCPTRS)) {			\
+ 		regs->ARM_r7 = r7;					\
+ 		regs->ARM_r8 = r8;					\
+ 		regs->ARM_r9 = r9;					\
+-- 
+2.25.1
+
diff --git a/target/linux/patches/6.4.12/armnommu-versatile.patch b/target/linux/patches/6.4.12/armnommu-versatile.patch
new file mode 100644
index 000000000..f8f10f50b
--- /dev/null
+++ b/target/linux/patches/6.4.12/armnommu-versatile.patch
@@ -0,0 +1,101 @@
+From 77c038d93769c92ef54cdbb50388564d1b37987b Mon Sep 17 00:00:00 2001
+From: Greg Ungerer <gerg@kernel.org>
+Date: Fri, 23 Sep 2016 13:37:34 +1000
+Subject: [PATCH] ARM: versatile: support configuring versatile machine for no-MMU
+
+Allow the arm versatile machine to be configured for no-MMU operation.
+
+Older kernels had the ability to build the versatile machine with the MMU
+disabled (!CONFIG_MMU). Recent changes to convert the versatile machine
+to device tree lost this ability. (Although older kernels could be built
+they did not run due to a bug in the IO_ADDRESS() mapping on this machine).
+
+The motivation for this is that the versatile machine is well supported
+in qemu. And this provides an excellent platform for development and
+testing no-MMU support on ARM in general.
+
+This patch adds a versatile platform selection in the upper level arm
+system type menu - where it appeared in older kernel versions - when
+configuring for the no-MMU case. There is no visible change to the way
+versatile is selected for the MMU enabled case.
+
+Signed-off-by: Greg Ungerer <gerg@kernel.org>
+---
+ arch/arm/Kconfig                    |   13 ++++++++++++-
+ arch/arm/include/asm/mach/map.h     |    1 +
+ arch/arm/mach-versatile/Kconfig     |    2 +-
+ arch/arm/mach-versatile/versatile.c |    4 ++++
+ 4 files changed, 18 insertions(+), 2 deletions(-)
+
+diff --git a/arch/arm/mach-versatile/versatile.c b/arch/arm/mach-versatile/versatile.c
+index 02ba68abe533..835b51bc597b 100644
+--- a/arch/arm/mach-versatile/versatile.c
++++ b/arch/arm/mach-versatile/versatile.c
+@@ -22,7 +22,11 @@
+ #include <asm/mach/map.h>
+ 
+ /* macro to get at MMIO space when running virtually */
++#ifdef CONFIG_MMU
+ #define IO_ADDRESS(x)		(((x) & 0x0fffffff) + (((x) >> 4) & 0x0f000000) + 0xf0000000)
++#else
++#define IO_ADDRESS(x)		(x)
++#endif
+ #define __io_address(n)		((void __iomem __force *)IO_ADDRESS(n))
+ 
+ /*
+diff --git a/arch/arm/include/asm/mach/map.h b/arch/arm/include/asm/mach/map.h
+index 2b8970d8e5a2..41844ab6aec5 100644
+--- a/arch/arm/include/asm/mach/map.h
++++ b/arch/arm/include/asm/mach/map.h
+@@ -60,6 +60,7 @@ extern int ioremap_page(unsigned long virt, unsigned long phys,
+ #else
+ #define iotable_init(map,num)	do { } while (0)
+ #define vm_reserve_area_early(a,s,c)	do { } while (0)
++#define debug_ll_io_init()	do { } while (0)
+ #endif
+ 
+ #endif
+diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
+index e24a9820e12f..342e1efa583a 100644
+--- a/arch/arm/Kconfig
++++ b/arch/arm/Kconfig
+@@ -307,12 +307,23 @@ config MMU
+ 	  Select if you want MMU-based virtualised addressing space
+ 	  support by paged memory management. If unsure, say 'Y'.
+ 
++choice
++	prompt "ARM system type"
++	depends on !MMU
++	default ARM_SINGLE_ARMV7M
++
+ config ARM_SINGLE_ARMV7M
+-	def_bool !MMU
++	bool "ARMv7-M based platforms (Cortex-M0/M3/M4)"
+ 	select ARM_NVIC
+ 	select CPU_V7M
+ 	select NO_IOPORT_MAP
+ 
++config ARM_SINGLE_ARM926
++	bool "ARM926 based platforms"
++	select CPU_ARM926T
++
++endchoice
++
+ config ARCH_MMAP_RND_BITS_MIN
+ 	default 8
+ 
+diff --git a/arch/arm/mach-versatile/Kconfig b/arch/arm/mach-versatile/Kconfig
+index b1519b4dc03a..2f1bf95daeb0 100644
+--- a/arch/arm/mach-versatile/Kconfig
++++ b/arch/arm/mach-versatile/Kconfig
+@@ -1,7 +1,7 @@
+ # SPDX-License-Identifier: GPL-2.0
+ config ARCH_VERSATILE
+ 	bool "ARM Ltd. Versatile family"
+-	depends on ARCH_MULTI_V5
++	depends on ARCH_MULTI_V5 || ARM_SINGLE_ARM926
+ 	depends on CPU_LITTLE_ENDIAN
+ 	select ARM_AMBA
+ 	select ARM_TIMER_SP804
+-- 
+2.25.1