Re: [PATCH 7/9] kvm: s390: Add CPU dump functionality

kernel test robot
2022-02-23T19:46:53Z

Hi Janosch,

I love your patch! Perhaps something to improve:

[auto build test WARNING on kvms390/next]
[also build test WARNING on next-20220222]
[cannot apply to kvm/master s390/features v5.17-rc5]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url: https://github.com/0day-ci/linux/commits/Janosch-Frank/kvm-s390-Add-PV-dump-support/20220223-172213
base: https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux.git next
config: s390-randconfig-r044-20220223 (https://download.01.org/0day-ci/archive/20220224/202202240337.wksMLgVn-lkp@intel.com/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project d271fc04d5b97b12e6b797c6067d3c96a8d7470e)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install s390 cross compiling tool for clang build
# apt-get install binutils-s390x-linux-gnu
# https://github.com/0day-ci/linux/commit/8e5a2c1d95d561cf1530c7a3427a1a367ab67364
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Janosch-Frank/kvm-s390-Add-PV-dump-support/20220223-172213
git checkout 8e5a2c1d95d561cf1530c7a3427a1a367ab67364
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=s390 SHELL=/bin/bash arch/s390/kvm/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

In file included from arch/s390/kvm/kvm-s390.c:23:
In file included from include/linux/kvm_host.h:41:
In file included from include/linux/kvm_para.h:5:
In file included from include/uapi/linux/kvm_para.h:37:
In file included from arch/s390/include/asm/kvm_para.h:25:
In file included from arch/s390/include/asm/diag.h:12:
In file included from include/linux/if_ether.h:19:
In file included from include/linux/skbuff.h:31:
In file included from include/linux/dma-mapping.h:10:
In file included from include/linux/scatterlist.h:9:
In file included from arch/s390/include/asm/io.h:75:
include/asm-generic/io.h:464:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __raw_readb(PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:477:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
~~~~~~~~~~ ^
include/uapi/linux/byteorder/big_endian.h:37:59: note: expanded from macro '__le16_to_cpu'
#define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x))
^
include/uapi/linux/swab.h:102:54: note: expanded from macro '__swab16'
#define __swab16(x) (__u16)__builtin_bswap16((__u16)(x))
^
In file included from arch/s390/kvm/kvm-s390.c:23:
In file included from include/linux/kvm_host.h:41:
In file included from include/linux/kvm_para.h:5:
In file included from include/uapi/linux/kvm_para.h:37:
In file included from arch/s390/include/asm/kvm_para.h:25:
In file included from arch/s390/include/asm/diag.h:12:
In file included from include/linux/if_ether.h:19:
In file included from include/linux/skbuff.h:31:
In file included from include/linux/dma-mapping.h:10:
In file included from include/linux/scatterlist.h:9:
In file included from arch/s390/include/asm/io.h:75:
include/asm-generic/io.h:490:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
~~~~~~~~~~ ^
include/uapi/linux/byteorder/big_endian.h:35:59: note: expanded from macro '__le32_to_cpu'
#define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x))
^
include/uapi/linux/swab.h:115:54: note: expanded from macro '__swab32'
#define __swab32(x) (__u32)__builtin_bswap32((__u32)(x))
^
In file included from arch/s390/kvm/kvm-s390.c:23:
In file included from include/linux/kvm_host.h:41:
In file included from include/linux/kvm_para.h:5:
In file included from include/uapi/linux/kvm_para.h:37:
In file included from arch/s390/include/asm/kvm_para.h:25:
In file included from arch/s390/include/asm/diag.h:12:
In file included from include/linux/if_ether.h:19:
In file included from include/linux/skbuff.h:31:
In file included from include/linux/dma-mapping.h:10:
In file included from include/linux/scatterlist.h:9:
In file included from arch/s390/include/asm/io.h:75:
include/asm-generic/io.h:501:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writeb(value, PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:511:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:521:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:609:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
readsb(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:617:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
readsw(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:625:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
readsl(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:634:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
writesb(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:643:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
writesw(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:652:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
writesl(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
>> arch/s390/kvm/kvm-s390.c:5088:5: warning: no previous prototype for function 'kvm_s390_handle_pv_vcpu_dump' [-Wmissing-prototypes]
int kvm_s390_handle_pv_vcpu_dump(struct kvm_vcpu *vcpu, struct kvm_pv_cmd *cmd)
^
arch/s390/kvm/kvm-s390.c:5088:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
int kvm_s390_handle_pv_vcpu_dump(struct kvm_vcpu *vcpu, struct kvm_pv_cmd *cmd)
^
static
13 warnings generated.

vim +/kvm_s390_handle_pv_vcpu_dump +5088 arch/s390/kvm/kvm-s390.c

5087
> 5088 int kvm_s390_handle_pv_vcpu_dump(struct kvm_vcpu *vcpu, struct kvm_pv_cmd *cmd)
5089 {
5090 struct kvm_s390_pv_dmp dmp;
5091 void *data;
5092 int ret;
5093
5094 /* Dump initialization is a prerequisite */
5095 if (!vcpu->kvm->arch.pv.dumping)
5096 return -EINVAL;
5097
5098 if (copy_from_user(&dmp, (__u8 __user *)cmd->data, sizeof(dmp)))
5099 return -EFAULT;
5100
5101 /* We only handle this subcmd right now */
5102 if (dmp.subcmd != KVM_PV_DUMP_CPU)
5103 return -EINVAL;
5104
5105 /* CPU dump length is the same as create cpu storage donation. */
5106 if (dmp.buff_len != uv_info.guest_cpu_stor_len)
5107 return -EINVAL;
5108
5109 data = vzalloc(uv_info.guest_cpu_stor_len);
5110 if (!data)
5111 return -ENOMEM;
5112
5113 ret = kvm_s390_pv_dump_cpu(vcpu, data, &cmd->rc, &cmd->rrc);
5114
5115 VCPU_EVENT(vcpu, 3, "PROTVIRT DUMP CPU %d rc %x rrc %x",
5116 vcpu->vcpu_id, cmd->rc, cmd->rrc);
5117
5118 if (ret) {
5119 vfree(data);
5120 return -EINVAL;
5121 }
5122
5123 /* On success copy over the dump data */
5124 if (copy_to_user((__u8 __user *)dmp.buff_addr, data, uv_info.guest_cpu_stor_len)) {
5125 vfree(data);
5126 return -EFAULT;
5127 }
5128
5129 vfree(data);
5130 return 0;
5131 }
5132

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0-DAY CI Kernel Test Service, Intel Corporation