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* From: Jeffrey Hsu <hsu@soda.berkeley.edu>alm1993-12-031-1/+4
| | | | | | | | | | | | | | | | | | | | | | The following patch adds the addr argument to signal handlers. The kernel with the patch is no more and no less in compliance or in violation of POSIX and ANSI C than the kernel before the patch. The added functionality this addr argument provides is quite useful. It enables an entire class of algorithms which use mprotect to trace memory references. Beside garbage collectors, I have heard of this technique being applied to debuggers and profilers. The only benchmarking I've performed is using akcl to compile maxima: without the kernel patch, it takes 7 hours to compile maxima, while with stratified garbage collection, it only takes 50 minutes. Basically, I can't think of a reason not to add the addr argument and there is a compelling need for it. If you find the patch acceptable, please let me know so I can send my FreeBSD akcl config files to wfs for inclusion in the core akcl release. The old 386BSD config files there won't work on either NetBSD or FreeBSD.
* Patch from Gene Stark:dg1993-11-281-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Subject: Page fault in PTE area fails in copyout Index: sys/i386/i386/trap.c FreeBSD-1.0.2 Description: Reading files of several megabytes into Emacs, or many small files all at once, would fail with "IO error - bad address". Repeat-By: The bug can be exercised by a test program that malloc()'s a 5MB chunk of memory, and then, without accessing the memory first, filling it with data from a file using read(). (I read 64k chunks from /dev/wd0d into successive 64k regions of the 5MB chunk.) The read() will fail with EFAULT at the first virtual address boundary that is a multiple of 0x400000. Fix: The problem was code in sys/i386/i386/trap.c that tries to figure out what kind of trap occurred and to handle it appropriately. It was interpreting any page fault with virtual address >= vm->vm_maxsaddr as being a user stack segment fault. In fact, addresses >= USRSTACK are in the user structure/PTE area, and if they are handled as stack faults, the proper PTE will not be paged in when it is supposed to be. This situation comes up in copyout() and copyoutstr(), if PTE's are accessed for the first time ever. The page fault on accessing the nonexistent PTE is mishandled as a stack fault, and then the fault that occurs on the subsequent access to the page itself causes copyout to fail with EFAULT.
* Make the LINT kernel compile with -W -Wreturn-type -Wcomment -Werror, andwollman1993-11-251-1/+3
| | | | add same (sans -Werror) to Makefile for future compilations.
* First steps in rewriting locore.s, and making info usefuldg1993-11-131-6/+48
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | when the machine panics. i386/i386/locore.s: 1) got rid of most .set directives that were being used like #define's, and replaced them with appropriate #define's in the appropriate header files (accessed via genassym). 2) added comments to header inclusions and global definitions, and global variables 3) replaced some hardcoded constants with cpp defines (such as PDESIZE and others) 4) aligned all comments to the same column to make them easier to read 5) moved macro definitions for ENTRY, ALIGN, NOP, etc. to /sys/i386/include/asmacros.h 6) added #ifdef BDE_DEBUGGER around all of Bruce's debugger code 7) added new global '_KERNend' to store last location+1 of kernel 8) cleaned up zeroing of bss so that only bss is zeroed 9) fix zeroing of page tables so that it really does zero them all - not just if they follow the bss. 10) rewrote page table initialization code so that 1) works correctly and 2) write protects the kernel text by default 11) properly initialize the kernel page directory, upages, p0stack PT, and page tables. The previous scheme was more than a bit screwy. 12) change allocation of virtual area of IO hole so that it is fixed at KERNBASE + 0xa0000. The previous scheme put it right after the kernel page tables and then later expected it to be at KERNBASE +0xa0000 13) change multiple bogus settings of user read/write of various areas of kernel VM - including the IO hole; we should never be accessing the IO hole in user mode through the kernel page tables 14) split kernel support routines such as bcopy, bzero, copyin, copyout, etc. into a seperate file 'support.s' 15) split swtch and related routines into a seperate 'swtch.s' 16) split routines related to traps, syscalls, and interrupts into a seperate file 'exception.s' 17) remove some unused global variables from locore that got inserted by Garrett when he pulled them out of some .h files. i386/isa/icu.s: 1) clean up global variable declarations 2) move in declaration of astpending and netisr i386/i386/pmap.c: 1) fix calculation of virtual_avail. It previously was calculated to be right in the middle of the kernel page tables - not a good place to start allocating kernel VM. 2) properly allocate kernel page dir/tables etc out of kernel map - previously only took out 2 pages. i386/i386/machdep.c: 1) modify boot() to print a warning that the system will reboot in PANIC_REBOOT_WAIT_TIME amount of seconds, and let the user abort with a key on the console. The machine will wait for ever if a key is typed before the reboot. The default is 15 seconds, but can be set to 0 to mean don't wait at all, -1 to mean wait forever, or any positive value to wait for that many seconds. 2) print "Rebooting..." just before doing it. kern/subr_prf.c: 1) remove PANICWAIT as it is deprecated by the change to machdep.c i386/i386/trap.c: 1) add table of trap type strings and use it to print a real trap/ panic message rather than just a number. Lot's of work to be done here, but this is the first step. Symbolic traceback is in the TODO. i386/i386/Makefile.i386: 1) add support in to build support.s, exception.s and swtch.s ...and various changes to various header files to make all of the above happen.
* splnone()'s in the trap code can be deadly. Save/restore previous prioritydg1993-11-041-5/+7
| | | | instead.
* Modified the "rude stack hack" that it only applies to addresses withinchmr1993-11-011-2/+4
| | | | | | the stack area and not memory above VM_MAXUSER_ADDRESS. That way, copyout and friends now work for pages whose page table entries have not yet been allocated/been paged out.
* genassym.c:rgrimes1993-10-151-33/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove NKMEMCLUSTERS, it is no longer define or used. locores.s: Fix comment on PTDpde and APTDpde to be pde instead of pte Add new equation for calculating location of Sysmap Remove Bill's old #ifdef garbage for counting up memory, that stuff will never be made to work and was just cluttering up the file. Add code that places the PTD, page table pages, and kernel stack below the 640k ISA hole if there is room for it, otherwise put this stuff all at 1MB. This fixes the 28K bogusity in the boot blocks, that can now go away! Fix the caclulation of where first is to be dependent on NKPDE so that we can skip over the above mentioned areas. The 28K thing is now 44K in size due to the increase in kernel virtual memory space, but since we no longer have to worry about that this is no big deal. Use if NNPX > 0 instead of ifdef NPX for floating point code. machdep.c Change the calculation of for the buffer cache to be 20% of all memory above 2MB and add back the upper limit of 2/5's of the VM_KMEM_SIZE so that we do not eat ALL of the kernel memory space on large memory machines, note that this will not even come into effect unless you have more than 32MB. The current buffer cache limit is 6.7MB due to this caclulation. It seems that we where erroniously allocating bufpages pages for buffer_map. buffer_map is UNUSED in this implementation of the buffer cache, but since the map is referenced in several if statements a quick fix was to simply allocate 1 vm page (but no real memory) to it. pmap.h Remove rcsid, don't want them in the kernel files! Removed some cruft inside an #ifdef DEBUGx that caused compiler errors if you where compiling this for debug. Use the #defines for PD_SHIFT and PG_SHIFT in place of constants. trap.c: Remove patch kit header and rcsid, fix $Id$. Now include "npx.h" and use NNPX for controlling the floating point code. Remove a now completly invalid check for a maximum virtual address, the virtual address now ends at 0xFFFFFFFF so there is no more MAX!! (Thanks David, I completly missed that one!) vm_machdep.c Remove patch kit header and rcsid, fix $Id$. Now include "npx.h" and use NNPX for controlling the floating point code. Replace several 0xFE00000 constants with KERNBASE
* Changed trap.c so that a panic will occur if we do not have hardwarergrimes1993-08-281-1/+5
| | | | | | | FP and we try to call the emulator when it is not compiled in. Removed the #if defined(i486) || defined(i387) that use to call the panic if we did not have a math emulator. Removed an extranious include of i386/i386/math_emu.h from math_emulate.c.
* * Applied fixes from Bruce Evans to fix COW bugs, >1MB kernel loading,dg1993-07-271-11/+73
| | | | | | | | | | | | | profiling, and various protection checks that cause security holes and system crashes. * Changed min/max/bcmp/ffs/strlen to be static inline functions - included from cpufunc.h in via systm.h. This change improves performance in many parts of the kernel - up to 5% in the networking layer alone. Note that this requires systm.h to be included in any file that uses these functions otherwise it won't be able to find them during the load. * Fixed incorrect call to splx() in if_is.c * Fixed bogus variable assignment to splx() in if_ed.c
* Initial import, 0.1 + pk 0.2.4-B1rgrimes1993-06-121-0/+547
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