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85b18d7b5e
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: 084ea4d611 ("s390/mm: add (non)secure page access exceptions handlers")
Cc: stable@vger.kernel.org
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
72 lines
2 KiB
C
72 lines
2 KiB
C
// SPDX-License-Identifier: GPL-2.0
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#include <asm/uv.h>
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#include <asm/facility.h>
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#include <asm/sections.h>
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/* will be used in arch/s390/kernel/uv.c */
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#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
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int __bootdata_preserved(prot_virt_guest);
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#endif
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#if IS_ENABLED(CONFIG_KVM)
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int __bootdata_preserved(prot_virt_host);
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#endif
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struct uv_info __bootdata_preserved(uv_info);
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void uv_query_info(void)
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{
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struct uv_cb_qui uvcb = {
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.header.cmd = UVC_CMD_QUI,
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.header.len = sizeof(uvcb)
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};
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if (!test_facility(158))
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return;
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/* rc==0x100 means that there is additional data we do not process */
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if (uv_call(0, (uint64_t)&uvcb) && uvcb.header.rc != 0x100)
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return;
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if (IS_ENABLED(CONFIG_KVM)) {
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memcpy(uv_info.inst_calls_list, uvcb.inst_calls_list, sizeof(uv_info.inst_calls_list));
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uv_info.uv_base_stor_len = uvcb.uv_base_stor_len;
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uv_info.guest_base_stor_len = uvcb.conf_base_phys_stor_len;
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uv_info.guest_virt_base_stor_len = uvcb.conf_base_virt_stor_len;
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uv_info.guest_virt_var_stor_len = uvcb.conf_virt_var_stor_len;
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uv_info.guest_cpu_stor_len = uvcb.cpu_stor_len;
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uv_info.max_sec_stor_addr = ALIGN(uvcb.max_guest_stor_addr, PAGE_SIZE);
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uv_info.max_num_sec_conf = uvcb.max_num_sec_conf;
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uv_info.max_guest_cpu_id = uvcb.max_guest_cpu_id;
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uv_info.uv_feature_indications = uvcb.uv_feature_indications;
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}
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#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
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if (test_bit_inv(BIT_UVC_CMD_SET_SHARED_ACCESS, (unsigned long *)uvcb.inst_calls_list) &&
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test_bit_inv(BIT_UVC_CMD_REMOVE_SHARED_ACCESS, (unsigned long *)uvcb.inst_calls_list))
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prot_virt_guest = 1;
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#endif
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}
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#if IS_ENABLED(CONFIG_KVM)
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static bool has_uv_sec_stor_limit(void)
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{
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/*
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* keep these conditions in line with setup_uv()
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*/
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if (!is_prot_virt_host())
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return false;
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if (is_prot_virt_guest())
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return false;
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if (!test_facility(158))
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return false;
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return !!uv_info.max_sec_stor_addr;
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}
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void adjust_to_uv_max(unsigned long *vmax)
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{
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if (has_uv_sec_stor_limit())
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*vmax = min_t(unsigned long, *vmax, uv_info.max_sec_stor_addr);
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}
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#endif
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