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| author | Janosch Frank <frankja@linux.ibm.com> | 2021-01-12 13:40:53 +0300 |
|---|---|---|
| committer | Vasily Gorbik <gor@linux.ibm.com> | 2021-07-05 13:44:23 +0300 |
| commit | 85b18d7b5e7ffefb2f076186511d39c4990aa005 (patch) | |
| tree | b725f7f8392d85e231b4f5c26c0c816ba75c87d1 /arch/s390/include/asm | |
| parent | 47f7c6cf0082e1d963d1761b6bc2a94480fc8671 (diff) | |
| download | linux-85b18d7b5e7ffefb2f076186511d39c4990aa005.tar.xz | |
s390: mm: Fix secure storage access exception handling
Turns out that the bit 61 in the TEID is not always 1 and if that's
the case the address space ID and the address are
unpredictable. Without an address and its address space ID we can't
export memory and hence we can only send a SIGSEGV to the process or
panic the kernel depending on who caused the exception.
Unfortunately bit 61 is only reliable if we have the "misc" UV feature
bit.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Fixes: 084ea4d611a3d ("s390/mm: add (non)secure page access exceptions handlers")
Cc: stable@vger.kernel.org
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Diffstat (limited to 'arch/s390/include/asm')
| -rw-r--r-- | arch/s390/include/asm/uv.h | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/arch/s390/include/asm/uv.h b/arch/s390/include/asm/uv.h index 7b98d4caee77..12c5f006c136 100644 --- a/arch/s390/include/asm/uv.h +++ b/arch/s390/include/asm/uv.h @@ -73,6 +73,10 @@ enum uv_cmds_inst { BIT_UVC_CMD_UNPIN_PAGE_SHARED = 22, }; +enum uv_feat_ind { + BIT_UV_FEAT_MISC = 0, +}; + struct uv_cb_header { u16 len; u16 cmd; /* Command Code */ @@ -97,7 +101,8 @@ struct uv_cb_qui { u64 max_guest_stor_addr; u8 reserved88[158 - 136]; u16 max_guest_cpu_id; - u8 reserveda0[200 - 160]; + u64 uv_feature_indications; + u8 reserveda0[200 - 168]; } __packed __aligned(8); /* Initialize Ultravisor */ @@ -274,6 +279,7 @@ struct uv_info { unsigned long max_sec_stor_addr; unsigned int max_num_sec_conf; unsigned short max_guest_cpu_id; + unsigned long uv_feature_indications; }; extern struct uv_info uv_info; |