5.15-stable patches

added patches:
	s390-kexec-handle-r_390_plt32dbl-rela-in-arch_kexec_apply_relocations_add.patch

diff --git a/queue-4.19/series b/queue-4.19/series
new file mode 100644 (file)
index 0000000..e69de29

diff --git a/queue-5.15/s390-kexec-handle-r_390_plt32dbl-rela-in-arch_kexec_apply_relocations_add.patch b/queue-5.15/s390-kexec-handle-r_390_plt32dbl-rela-in-arch_kexec_apply_relocations_add.patch
new file mode 100644 (file)
index 0000000..d3aa469
--- /dev/null
+++ b/queue-5.15/s390-kexec-handle-r_390_plt32dbl-rela-in-arch_kexec_apply_relocations_add.patch
@@ -0,0 +1,79 @@
+From abf0e8e4ef25478a4390115e6a953d589d1f9ffd Mon Sep 17 00:00:00 2001
+From: Alexander Egorenkov <egorenar@linux.ibm.com>
+Date: Thu, 9 Dec 2021 08:38:17 +0100
+Subject: s390/kexec: handle R_390_PLT32DBL rela in arch_kexec_apply_relocations_add()
+
+From: Alexander Egorenkov <egorenar@linux.ibm.com>
+
+commit abf0e8e4ef25478a4390115e6a953d589d1f9ffd upstream.
+
+Starting with gcc 11.3, the C compiler will generate PLT-relative function
+calls even if they are local and do not require it. Later on during linking,
+the linker will replace all PLT-relative calls to local functions with
+PC-relative ones. Unfortunately, the purgatory code of kexec/kdump is
+not being linked as a regular executable or shared library would have been,
+and therefore, all PLT-relative addresses remain in the generated purgatory
+object code unresolved. This leads to the situation where the purgatory
+code is being executed during kdump with all PLT-relative addresses
+unresolved. And this results in endless loops within the purgatory code.
+
+Furthermore, the clang C compiler has always behaved like described above
+and this commit should fix kdump for kernels built with the latter.
+
+Because the purgatory code is no regular executable or shared library,
+contains only calls to local functions and has no PLT, all R_390_PLT32DBL
+relocation entries can be resolved just like a R_390_PC32DBL one.
+
+* https://refspecs.linuxfoundation.org/ELF/zSeries/lzsabi0_zSeries/x1633.html#AEN1699
+
+Relocation entries of purgatory code generated with gcc 11.3
+------------------------------------------------------------
+
+$ readelf -r linux/arch/s390/purgatory/purgatory.o
+
+Relocation section '.rela.text' at offset 0x370 contains 5 entries:
+  Offset          Info           Type           Sym. Value    Sym. Name + Addend
+00000000005c  000c00000013 R_390_PC32DBL     0000000000000000 purgatory_sha_regions + 2
+00000000007a  000d00000014 R_390_PLT32DBL    0000000000000000 sha256_update + 2
+00000000008c  000e00000014 R_390_PLT32DBL    0000000000000000 sha256_final + 2
+000000000092  000800000013 R_390_PC32DBL     0000000000000000 .LC0 + 2
+0000000000a0  000f00000014 R_390_PLT32DBL    0000000000000000 memcmp + 2
+
+Relocation entries of purgatory code generated with gcc 11.2
+------------------------------------------------------------
+
+$ readelf -r linux/arch/s390/purgatory/purgatory.o
+
+Relocation section '.rela.text' at offset 0x368 contains 5 entries:
+  Offset          Info           Type           Sym. Value    Sym. Name + Addend
+00000000005c  000c00000013 R_390_PC32DBL     0000000000000000 purgatory_sha_regions + 2
+00000000007a  000d00000013 R_390_PC32DBL     0000000000000000 sha256_update + 2
+00000000008c  000e00000013 R_390_PC32DBL     0000000000000000 sha256_final + 2
+000000000092  000800000013 R_390_PC32DBL     0000000000000000 .LC0 + 2
+0000000000a0  000f00000013 R_390_PC32DBL     0000000000000000 memcmp + 2
+
+Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
+Reported-by: Tao Liu <ltao@redhat.com>
+Suggested-by: Philipp Rudo <prudo@redhat.com>
+Reviewed-by: Philipp Rudo <prudo@redhat.com>
+Cc: <stable@vger.kernel.org>
+Link: https://lore.kernel.org/r/20211209073817.82196-1-egorenar@linux.ibm.com
+Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ arch/s390/kernel/machine_kexec_file.c |    4 ++++
+ 1 file changed, 4 insertions(+)
+
+--- a/arch/s390/kernel/machine_kexec_file.c
++++ b/arch/s390/kernel/machine_kexec_file.c
+@@ -312,6 +312,10 @@ int arch_kexec_apply_relocations_add(str
+               addr = section->sh_addr + relas[i].r_offset;
+ 
+               r_type = ELF64_R_TYPE(relas[i].r_info);
++
++              if (r_type == R_390_PLT32DBL)
++                      r_type = R_390_PC32DBL;
++
+               ret = arch_kexec_do_relocs(r_type, loc, val, addr);
+               if (ret) {
+                       pr_err("Unknown rela relocation: %d\n", r_type);

diff --git a/queue-5.15/series b/queue-5.15/series
new file mode 100644 (file)
index 0000000..c6a767d
--- /dev/null
+++ b/queue-5.15/series
@@ -0,0 +1 @@
+s390-kexec-handle-r_390_plt32dbl-rela-in-arch_kexec_apply_relocations_add.patch