Hi Dave, Noticed that raw ramdumps of 5.4 kernel aren't working with crash tip. With the patches attached, I could get it working. Please take a look. Thanks, Vinayak

Hi I made almost the same patch to fix the problem with arm64 in version 5.4... One very small change can merged together,vmemmap_start has a little error: [arch/arm64/include/asm/memory.h] 56 #define VMEMMAP_START (-VMEMMAP_SIZE - SZ_2M) in crash arm64.c - vmemmap_start = (-vmemmap_size); + vmemmap_start = (-vmemmap_size - MEGABYTES(2));

BTW,in arm64_VTOP,it's easier to use the physvirt_offset directly @@ -1148,8 +1155,7 @@ arm64_VTOP(ulong addr) } if (addr >= machdep->machspec->page_offset) - return machdep->machspec->phys_offset - + (addr - machdep->machspec->page_offset); + return (addr + machdep->machspec->physvirt_offset);

________________________________________ From: crash-utility-bounces(a)redhat.com <crash-utility-bounces(a)redhat.com&gt; on behalf of Dave Anderson <anderson(a)redhat.com&gt; Sent: Saturday, April 18, 2020 0:32 To: Discussion list for crash utility usage, maintenance and development Subject: [External Mail][????] Re: [Crash-utility] ramdump support for va_bits_actual ----- Original Message ----- > Hi Dave, > > Noticed that raw ramdumps of 5.4 kernel aren't working with crash tip. > With the patches attached, I could get it working. Please take a look. > > Thanks, > Vinayak > Hi Vinayak, A couple quick questions come to mind... First, I haven't checked all possible READMEM plugins, but for example, if this function is run on a live system, the -1 file descriptor would cause the READMEM() call to fail: static void +arm64_calc_physvirt_offset(void) +{ + struct machine_specific *ms = machdep->machspec; + ulong physvirt_offset; + struct syment *sp; + + ms->physvirt_offset = ms->phys_offset - ms->page_offset; + + if ((sp = kernel_symbol_search("physvirt_offset")) && + machdep->machspec->kimage_voffset) { + if (READMEM(-1, &physvirt_offset, sizeof(physvirt_offset), + sp->value, sp->value - + machdep->machspec->kimage_voffset) > 0) { + ms->physvirt_offset = physvirt_offset; + } + } + + if (CRASHDEBUG(1)) + fprintf(fp, "using %lx as physvirt_offset\n", ms->physvirt_offset); +} And here -- are you missing some brackets? (run "make warn") But regardless of that, why are you setting it back to 48 if it's greater than 48? diff --git a/arm64.c b/arm64.c index 31d6e90..04efc13 100644 --- a/arm64.c +++ b/arm64.c @@ -4011,6 +4011,7 @@ arm64_calc_virtual_memory_ranges(void) struct machine_specific *ms = machdep->machspec; ulong value, vmemmap_start, vmemmap_end, vmemmap_size, vmalloc_end; char *string; + int ret; ulong PUD_SIZE = UNINITIALIZED; if (!machdep->machspec->CONFIG_ARM64_VA_BITS) { @@ -4018,6 +4019,12 @@ arm64_calc_virtual_memory_ranges(void) value = atol(string); free(string); machdep->machspec->CONFIG_ARM64_VA_BITS = value; + } else if (kt->ikconfig_flags & IKCONFIG_AVAIL) { + if ((ret = get_kernel_config("CONFIG_ARM64_VA_BITS", + &string)) == IKCONFIG_STR) + machdep->machspec->CONFIG_ARM64_VA_BITS = atol(string); + if (machdep->machspec->CONFIG_ARM64_VA_BITS > 48) + machdep->machspec->CONFIG_ARM64_VA_BITS = 48; } } Thanks, Dave -- Crash-utility mailing list Crash-utility(a)redhat.com https://www.redhat.com/mailman/listinfo/crash-utility #/******本邮件及其附件含有小米公司的保密信息，仅限于发送给上面地址中列出的个人或群组。禁止任何其他人以任何形式使用（包括但不限于全部或部分地泄露、复制、或散发）本邮件中的信息。如果您错收了本邮件，请您立即电话或邮件通知发件人并删除本邮件！ This e-mail and its attachments contain confidential information from XIAOMI, which is intended only for the person or entity whose address is listed above. Any use of the information contained herein in any way (including, but not limited to, total or partial disclosure, reproduction, or dissemination) by persons other than the intended recipient(s) is prohibited. If you receive this e-mail in error, please notify the sender by phone or email immediately and delete it!******/# -- Crash-utility mailing list Crash-utility(a)redhat.com https://www.redhat.com/mailman/listinfo/crash-utility

Hi,Dave I don't quite understand how you said to read vmemmap,VMEMMAP_START is a macro definition,or it's a constant,in crash-utility vmemmap_start is a wrong value,this may cause arm64_IS_VMALLOC_ADDR return wrong status

We can get physvirt_offset earlier,in my patch,after calling arm64_calc_phys_offset we can initialize physvirt_offset,in this time,kimage_offset,page_offset and phys_offset are ready,such as: @@ -391,6 +391,13 @@ arm64_init(int when) ms = machdep->machspec; + if (kernel_symbol_exists("physvirt_offset") && + readmem(symbol_value("physvirt_offset"), KVADDR, + &value, sizeof(ulong), "physvirt_offset", QUIET|RETURN_ON_ERROR)) + ms->physvirt_offset = value; + else + ms->physvirt_offset = ms->phys_offset -> ms->page_offset;

________________________________________ From: crash-utility-bounces(a)redhat.com <crash-utility-bounces(a)redhat.com&gt; on behalf of Dave Anderson <anderson(a)redhat.com&gt; Sent: Sunday, April 19, 2020 1:03 To: Discussion list for crash utility usage, maintenance and development Subject: [营销邮件] Re: [Crash-utility] [External Mail][????] Re: ramdump support for va_bits_actual ----- Original Message ----- > Hi > I made almost the same patch to fix the problem with arm64 in version > 5.4... > > One very small change can merged together,vmemmap_start has a little error: > [arch/arm64/include/asm/memory.h] > 56 #define VMEMMAP_START (-VMEMMAP_SIZE - SZ_2M) > in crash arm64.c > - vmemmap_start = (-vmemmap_size); > + vmemmap_start = (-vmemmap_size - MEGABYTES(2)); Can't we just read the value of "vmemmap"? If not, what is the difference between the calculated value above and the value of vmemmap? > > > BTW,in arm64_VTOP,it's easier to use the physvirt_offset directly > @@ -1148,8 +1155,7 @@ arm64_VTOP(ulong addr) > > } > > if (addr >= machdep->machspec->page_offset) > - return machdep->machspec->phys_offset > - + (addr - machdep->machspec->page_offset); > + return (addr + machdep->machspec->physvirt_offset); Unfortunately that's not possible, because there is at least one arm64_VTOP() call *before* the new machdep->machspec->physvirt_offset gets initialized, which I presume is why Vinayak's patch checks whether it's non-zero first. Dave > ________________________________________ > From: crash-utility-bounces(a)redhat.com <crash-utility-bounces(a)redhat.com&gt; > on > behalf of Dave Anderson <anderson(a)redhat.com&gt; > Sent: Saturday, April 18, 2020 0:32 > To: Discussion list for crash utility usage, maintenance and development > Subject: [External Mail][????] Re: [Crash-utility] ramdump support for > va_bits_actual > > ----- Original Message ----- > > Hi Dave, > > > > Noticed that raw ramdumps of 5.4 kernel aren't working with crash tip. > > With the patches attached, I could get it working. Please take a look. > > > > Thanks, > > Vinayak > > > > Hi Vinayak, > > A couple quick questions come to mind... > > First, I haven't checked all possible READMEM plugins, but for example, if > this > function is run on a live system, the -1 file descriptor would cause the > READMEM() > call to fail: > > static void > +arm64_calc_physvirt_offset(void) > +{ > + struct machine_specific *ms = machdep->machspec; > + ulong physvirt_offset; > + struct syment *sp; > + > + ms->physvirt_offset = ms->phys_offset - ms->page_offset; > + > + if ((sp = kernel_symbol_search("physvirt_offset")) && > + machdep->machspec->kimage_voffset) { > + if (READMEM(-1, &physvirt_offset, sizeof(physvirt_offset), > + sp->value, sp->value - > + machdep->machspec->kimage_voffset) > 0) { > + ms->physvirt_offset = physvirt_offset; > + } > + } > + > + if (CRASHDEBUG(1)) > + fprintf(fp, "using %lx as physvirt_offset\n", > ms->physvirt_offset); > +} > > And here -- are you missing some brackets? (run "make warn") > > But regardless of that, why are you setting it back to 48 if it's greater > than 48? > > diff --git a/arm64.c b/arm64.c > index 31d6e90..04efc13 100644 > --- a/arm64.c > +++ b/arm64.c > @@ -4011,6 +4011,7 @@ arm64_calc_virtual_memory_ranges(void) > struct machine_specific *ms = machdep->machspec; > ulong value, vmemmap_start, vmemmap_end, vmemmap_size, vmalloc_end; > char *string; > + int ret; > ulong PUD_SIZE = UNINITIALIZED; > > if (!machdep->machspec->CONFIG_ARM64_VA_BITS) { > @@ -4018,6 +4019,12 @@ arm64_calc_virtual_memory_ranges(void) > value = atol(string); > free(string); > machdep->machspec->CONFIG_ARM64_VA_BITS = value; > + } else if (kt->ikconfig_flags & IKCONFIG_AVAIL) { > + if ((ret = > get_kernel_config("CONFIG_ARM64_VA_BITS", > + &string)) == IKCONFIG_STR) > + machdep->machspec->CONFIG_ARM64_VA_BITS = > atol(string); > + if (machdep->machspec->CONFIG_ARM64_VA_BITS > > > 48) > + > machdep->machspec->CONFIG_ARM64_VA_BITS > = 48; > } > } > > Thanks, > Dave > > -- > Crash-utility mailing list > Crash-utility(a)redhat.com > https://www.redhat.com/mailman/listinfo/crash-utility > > #/******本邮件及其附件含有小米公司的保密信息，仅限于发送给上面地址中列出的个人或群组。禁止任何其他人以任何形式使用（包括但不限于全部或部分地泄露、复制、或散发）本邮件中的信息。如果您错收了本邮件，请您立即电话或邮件通知发件人并删除本邮件！ > This e-mail and its attachments contain confidential information from > XIAOMI, which is intended only for the person or entity whose address is > listed above. Any use of the information contained herein in any way > (including, but not limited to, total or partial disclosure, reproduction, > or dissemination) by persons other than the intended recipient(s) is > prohibited. If you receive this e-mail in error, please notify the sender > by > phone or email immediately and delete it!******/# > > -- > Crash-utility mailing list > Crash-utility(a)redhat.com > https://www.redhat.com/mailman/listinfo/crash-utility -- Crash-utility mailing list Crash-utility(a)redhat.com https://www.redhat.com/mailman/listinfo/crash-utility #/******本邮件及其附件含有小米公司的保密信息，仅限于发送给上面地址中列出的个人或群组。禁止任何其他人以任何形式使用（包括但不限于全部或部分地泄露、复制、或散发）本邮件中的信息。如果您错收了本邮件，请您立即电话或邮件通知发件人并删除本邮件！ This e-mail and its attachments contain confidential information from XIAOMI, which is intended only for the person or entity whose address is listed above. Any use of the information contained herein in any way (including, but not limited to, total or partial disclosure, reproduction, or dissemination) by persons other than the intended recipient(s) is prohibited. If you receive this e-mail in error, please notify the sender by phone or email immediately and delete it!******/# -- Crash-utility mailing list Crash-utility(a)redhat.com https://www.redhat.com/mailman/listinfo/crash-utility

Hi Dave, On Sat, Apr 18, 2020 at 2:08 PM Dave Anderson <anderson(a)redhat.com&gt; wrote: > > > > ----- Original Message ----- > > Hi Dave, > > > > Noticed that raw ramdumps of 5.4 kernel aren't working with crash tip. > > With the patches attached, I could get it working. Please take a look. > > > > Thanks, > > Vinayak > > > > Hi Vinayak, > > A couple quick questions come to mind... > > First, I haven't checked all possible READMEM plugins, but for example, if > this > function is run on a live system, the -1 file descriptor would cause the > READMEM() > call to fail: I changed it like this and it works for ramdump. I don't actually have a live setup to try this. Let me try to set up one. diff --git a/arm64.c b/arm64.c index 04efc13..fce3f8e 100644 --- a/arm64.c +++ b/arm64.c @@ -981,7 +981,7 @@ arm64_calc_physvirt_offset(void) if ((sp = kernel_symbol_search("physvirt_offset")) && machdep->machspec->kimage_voffset) { - if (READMEM(-1, &physvirt_offset, sizeof(physvirt_offset), + if (READMEM(pc->mfd, &physvirt_offset, sizeof(physvirt_offset), sp->value, sp->value - machdep->machspec->kimage_voffset) > 0) { ms->physvirt_offset = physvirt_offset; > > static void > +arm64_calc_physvirt_offset(void) > +{ > + struct machine_specific *ms = machdep->machspec; > + ulong physvirt_offset; > + struct syment *sp; > + > + ms->physvirt_offset = ms->phys_offset - ms->page_offset; > + > + if ((sp = kernel_symbol_search("physvirt_offset")) && > + machdep->machspec->kimage_voffset) { > + if (READMEM(-1, &physvirt_offset, sizeof(physvirt_offset), > + sp->value, sp->value - > + machdep->machspec->kimage_voffset) > 0) { > + ms->physvirt_offset = physvirt_offset; > + } > + } > + > + if (CRASHDEBUG(1)) > + fprintf(fp, "using %lx as physvirt_offset\n", ms->physvirt_offset); > +} > > And here -- are you missing some brackets? (run "make warn") > I did try "make warn" and it does not show any issues.Am I missing something?

> But regardless of that, why are you setting it back to 48 if it's greater > than 48? > I did that because machspec->CONFIG_ARM64_VA_BITS is used for calculation of vmemmap size. In kernel vmemmap size is calculated using VA_BITS_MIN and it is defined like this #if VA_BITS > 48 #define VA_BITS_MIN (48) #else #define VA_BITS_MIN (VA_BITS) #endif But I realize now that its not the right thing to do, because machspec->CONFIG_ARM64_VA_BITS is later used in arm64_calc_VA_BITS to verify machspec->VA_BITS. So what about this ? diff --git a/arm64.c b/arm64.c index 04efc13..a35a30e 100644 --- a/arm64.c +++ b/arm64.c @@ -4023,8 +4023,6 @@ arm64_calc_virtual_memory_ranges(void) if ((ret = get_kernel_config("CONFIG_ARM64_VA_BITS", &string)) == IKCONFIG_STR) machdep->machspec->CONFIG_ARM64_VA_BITS = atol(string); - if (machdep->machspec->CONFIG_ARM64_VA_BITS > 48) - machdep->machspec->CONFIG_ARM64_VA_BITS = 48; } } @@ -4049,7 +4047,12 @@ arm64_calc_virtual_memory_ranges(void) #define STRUCT_PAGE_MAX_SHIFT 6 if (ms->VA_BITS_ACTUAL) { - vmemmap_size = (1UL) << (ms->CONFIG_ARM64_VA_BITS - machdep->pageshift - 1 + STRUCT_PAGE_MAX_SHIFT); + ulong va_bits_min = 48; + + if (machdep->machspec->CONFIG_ARM64_VA_BITS < 48) + va_bits_min = ms->CONFIG_ARM64_VA_BITS; + + vmemmap_size = (1UL) << (va_bits_min - machdep->pageshift - 1 + STRUCT_PAGE_MAX_SHIFT); vmalloc_end = (- PUD_SIZE - vmemmap_size - KILOBYTES(64)); vmemmap_start = (-vmemmap_size); ms->vmalloc_end = vmalloc_end - 1;

Yeah, that looks reasonable. But what about the parallel discussion re: vmemmap_start? https://www.redhat.com/archives/crash-utility/2020-April/msg00064.html

Can you send in an updated patch set with all fixes applied?